I believe in both god, and that the earth incredibly old

Clearly, you were taught by people who think they know more than they actually do.

Meh. 🤷‍♂️

Reading comprehension doesn't seem to be one of your strong points. I didn't actually call you egotistical, willfully ignorant or a moron, but anyone who studies the Bible must develop the skills of filling in blanks and drawing conclusions based on nothing much at all, so I guess it's understandable that you believe I did.

FWIW, I'm fine with people believing whatever nonsense they choose. As long as you don't try to cram it down my throat or anyone else's, that's fine by me.

I recently learned about the Great Tartarian Mud Flood and the reset of 1834. From now on, whenever I come across someone who enjoys believing in BS that lacks any credible, supporting evidence, I'm going to suggest they investigate it. Check it out, brah, it might be right up your alley.

This is merely the teleological argument for the existence of a deity, also known as intelligent design or watchmaker argument.

David Hume started shooting holes in that argument more than 300 years ago, and countless philosophers have continued to shred it with logic in the centuries ever since.

But of course people are free to ignore all that and hand-wave away the complete lack of any hard scientific evidence supporting the existence of a deity as either the prime-mover of the cosmos or the existence of life on earth. Some people really desperately need to believe that they are super-important and their existence is super-significant, even though our time on this piffling little rock orbiting one very normal star in one of a hundred billion galaxies isn't even a blink of the eye in the life of the universe.

You've "always heard that the Earth must be young".

That makes it sound like this is an assertion that you've never actually investigated, but rather that you've simply accepted what someone who claimed some degree of expertise told you was true. And yet you say in your OP title that you accept that the earth is very old.

Anyone who spent time studying cosmology, geology, palaeontology, archaeology and evolutionary biology would come to realise that countless indisputable facts all fit together in such logical, consistent way that the story told in the opening verses of Genesis cannot be anything more than just one of countless creation myths.

However, such an investigation does require effort and some degree of dedication. Most people find it far easier to click Like and Subscribe, continue to put their cash in the collection plate and gulp down whatever guff allows them to believe that Earth is the true centre of the universe, humans are the pinnacle of God's creation and they are vitally important to Him.