Atoms could be any number of billions of years old; the Bible doesn't preclude that the atoms first covered by verse 1 of Genesis, didn't sit like that for billions of years, before verse 2.
However, evidence (geological, astronomical, population numbers, population locations, races, animal kinds/species and fossil records) supports the idea that the origin of life as we know it, animal and vegetation, is more like 6,000 thousand years old, with a major adjustment 4,500 years ago, where the human and land animal population dropped to nearly nothing
and our geological formations were rapidly pummelled.
It's worth then addressing why we hear so often that the universe is so much older...
The common dating methods, which date rocks and bones as millions or billions of years old, all have major flaws.
Since time was made/"injected from outside", along with matter and energy, how long did it take to make time? It is immeasurable from within time and irrelevant outside of time.
Also, ageing atoms is different than the ageing their formation, position and groupings. As stated above, the Bible doesn't preclude the building blocks of matter, used in creation, from being anything from moments old to any number of billions years old.
But that an atom is very old, even if ignoring how poor our dating methods are, that it has sat there with the others like it, in that orientation for the same length of time, isn't a given.
Radiometric dating, radioactive dating or radioisotope dating, Examples:
Uranium–lead dating method.
Samarium–neodymium dating method.
Potassium–argon dating method.
Rubidium–strontium dating method.
Uranium–thorium dating method.
Radiocarbon dating method.
Fission track dating method.
Chlorine-36 dating method.
These methods have a lack of evidence, unprovable exponential extrapolations and dogmatic assumptions made on original parent daughter ratios and assumptions made on rate of decay having remained unchanged.
The different dating mechanisms can give different dates for the same rock.
For example the 1954 lava flows in New Zealand have been recorded as 3.5 million years old! This could be due to elements trapped in lava from the mantle of the earth and not being accounted for in these measurements.
The speed of light is slowing down.
This is a recent finding and not widely accepted (yet). But the implication is huge, in terms of experience of time and the effects on our age and various dating methods above.
The speed of light is not a constant, it is slowing down. Measurements have become more accurate, but the mean of each measurement, has been getting smaller over time. Recognised in reputable scientific journals. Amongst other things, this makes various carbon dating methods terribly inaccurate for long ages (because C - the speed of light, impacts the resonance and hence decay in atoms).
It also raises the possibility of time having “passed more quickly” compared to today, only a few thousand years ago, adding other possibilities as to the apparent long-age of the universe.
The proof of evolution is the age of the rocks in which the fossils are found. This is circular.
The age of rock is determined from the age of a fossil, which is determined by evolution. The assumption of evolution is therefore the main evidence for evolution.
Not enough mud on the sea floor
There's not enough mud on the sea floor from the alleged billions of years of sediment and dead animals.
Ocean Salinity
Salinity (amount of salt) in the oceans suggests they are only a few thousand years old.
Trees
Trees are the oldest living thing on the planet, the oldest of which is said to be 4500 years old, the time of the flood!
Limestone
Limestone is sedimentary rock. It precipitates out of water and is spread worldwide, due to the flood.
Mississippi delta sediment
Mississippi Delta, sediment deposited into the Mexican Gulf each year, suggests it's 4,000 years old.
Helium content in the world
Is consistent with biblical timescales, not an old earth.
Helium in the wrong places
It just is, check if you like.
Geological formations
The grand canyon and a more "recent" one. It can be shown that the rock units exposed in the walls, must have been formed very rapidly under catastrophic hydraulic (watery) erosion.
Uluru the same. In line with the biblical flood narative.
Formation of granite, coal, oil and diamonds
Can be explained to occur in only hundreds to thousands of years, when accounting for it originating as magma (granite that is) and rapid water cooling.
Earth's Magnetic Field
Earth's magnetic field half life shows the earth is less than 10,000 years old. if it went back 20,000 years, the joule heat would liquefy the earth
Horticulture
Lammerts (the father of modern rose breeding), had to ignore evolutionist principals and show that immediate change could be effected (within the kind/type of roses).
Radioactive halos
Radioactive halos, Primordial Polonium 218 has been found on mica and fluorite. Polonium 218 has a half life of 3minutes. This is evidence of instantaneous crystallisation of the host granite concurrent with the formation of the polonium. This speaks of instantaneous creation.
World population.
Records, current and projected backward world populations give the world population as that of Noah's family (8) at the time of the flood (2348 BC or 4371 years ago as of 2023).
Works forwards as well, if we assume that the population doubles every 150 years, we see, again, that starting with only Noah and his family in 2500 BC, 4,500 years is more than enough time for the present population to reach 6.5 billion.
However, if Humans have been around 50,000 years, at the above rate we'd be at 10 to the power 100 (10 with 100 zeros) of us.
Skin colour and ethnicity.
Virtually all scientists now agree all humans originated from the same "pack". Evolutionists will say the divergent traits evolved over tens of thousands of years, but evidence supports that the divergence could have occurred over just a few thousand years.
Human and animal dispersion to far flung continents and islands.
Imagine a global year long flood, with water coming up from the crust as well as down as rain, probable volcanic eruptions and tectonic plate shifts. This would account for terrain after the flood, being very different than before. It would also likely lead to an accumulation of ice, like an ice age, but only hundreds of years long, not thousands. With ice and waters later receding, human groups could easily be dispersed and cut off from one another.
Fossil records consistent with there having been the flood.
There's no food found with the animal fossils, how did they survive?
Sea life found in the Himalayas. All more easily explained by a global flood speading sediment quickly and catastrophically.
Fossil records consistent with dinosaurs having lived with humans.
Paluxy River 'footprints' show humans and dinosaurs were around at the same time.
This probably accounts for most cultures having similar documented legends of dragon like creatures. For example ancient engraved-in-rock drawings of long necked dinosaurs, with their necks entwined together (so drawn as if they were alive), that look like diplodocus' (not giraffes) have been found in the ruins of ancient cultures on opposite sides of the earth.
Not enough stone age skeletons
There would have to be more than have been found.
Moon dust depth
Moon dust due to UV light and x-rays, would be several miles deep (if so old) but only a depth aligned to a few thousand years was found during the moon landing.
The distance of the Moon from the Earth
The moon moves away about 4cm a year. It would have been in contact with the earth 1.3 billion years ago or making monstrous tides, 1 billion years ago, which no one believes.
The brightness of the Sun
Calcs show the Sun is 40% brighter than when it was allegedly formed 4.5billion years ago. And 30% brighter than when life allegedly emerged on Earth 3.5 billion years ago. Based on the current atmosphere the average temp would have been below zero. We must assume there were more greenhouse gases to keep life warmed and then evolved over billions of years to maintain the temperature! a 6,000 year old universe is easier to believe.
Comets not having all worn out.
Even with generous assumptions, all comets would have worn out after a few tens of millions of years, not the proposed 4.5 billion years of the universe.
Supernova remnants in our Galaxy.
Solar nebula, when a star explodes. We can count these now. They take place once every 26 years. There are only enough to account for 6,000 to 7,000 years, not millions of years.
Missing neutrinos from the sun
There would be more missing if it was as old as we're told.
The oscillation period of the sun
Matches a young universe, not old universe.
Lack of Moon meteorite debris
There would be more craters if the moon had been exposed where it is, as long as we led to believe.
Light appearing to have travelled for many light years.
In the same way blood had to be flowing instantly and Adam's body appear developed and 30 years old, so light travelling from afar could have been given the "signature" of having done so, without actually having done so.
Using current current physics to date pre-physics events.
Stuff might look older, counting as if they've always been subject to the scientific laws the same as they are today, but the inauguration process may have skewed our calculations.
The bringing about of the laws of thermodynamics (entropy and decay from an initial start) during the 6 days of creation, or possibly later as part of the Fall, could leave a "finger print" in what is observable today, that due to their very nature of being, institutional and outside the "now operational laws of physics", hides their real age (makes them appear older).
The appearance of age, necessary in near instantaneous creation.
The first trees did not come from seeds. The first mammals did not come from embryos. Adam was not an infant on his first day. All things appeared as if they had been in existence before their day of creation.
Including supernovas/explosions appearing to be from 150,000 years ago.
Movies are like this and we readily accept this and do not feel deceived.
The action starts at some point and continues to the end of the program.