The Bible vs history books question

So to preface, I think I've always known deep down that I never really believed in God. And it's only in the last couple of years I've felt semi-comfortable calling myself an atheist. My dad is Christian and he threw at me the classic, "There's more evidence to Jesus existing than Caesar" blah blah. That's a whole other thing.

But it got me thinking, since the Bible is just a book and not proof of anything... is that the same for all ancient or just slightly older historical texts? I find myself being skeptical of not only the Bible, but all history lately . Especially history where no one that is alive today has witnessed.

How do we know any of it really happened? And also, why is it that some us still believe in very old historical events that are now only mentioned in texts, but not the Bible? Is it just the unrealistic nature of it?

It's clear the Bible was mostly influenced by the people who wrote it and not necessarily proof of the event happening. Do you think we can say the same about all of pieces of history?

I think I'm still struggling and just questioning everything I once knew.

Edit: Thank you all so much for your responses and for all future responses! This is all so helpful and I'm definitely going to be doing some more reading on all of this. It's so helpful for someone like me, who is still learning.