The Bible isn’t actually one book. It’s a collection of 66 scrolls and letters which was gathered together around 300AD. In fact “Bible” is a transliteration of the ancient Greek word “biblia” which just means “books”.

It was written by about 40 different people, over a period of about 1600 years. So no chance for conspiracy there - there is no way they knew each other, or got together to get their stories matching up.

Even though the Bible is the best selling book in the world year after year, the guys who actually wrote it never made any money out of it. In fact, most of them were killed or mistreated for what they wrote.

There are two parts to the Bible. The Old Testament and the New Testament. A testament is like a contract. The old contract between Yahweh (God) and his people was that if they kept “The Law” he would look after them. The Law is basically the 10 commandments, but actually it’s a whole list of rules and regulations about what is right and wrong, and what to do if you break them so Yahweh will overlook your “sin”.
The new contract is that Yeshua (Jesus) fulfilled that Law, so now you can have a good relationship with Yahweh directly just by trusting in what Yeshua did for you. Regardless of whether you do the right thing or not, your relationship is founded on what Yeshua did 2,000 years ago, not on what you do today. It’s a totally different way of living right with God.
So the first 39 “books” of the Bible are about the old contract. The last 27 are about the new contract. Although the first 4 books of the New Testament are sort of transition books. Sometimes Yeshua is talking with Jews about their old contract, and how they need a new one. The new contract starts at the end of those first 4 books. After Yeshua is executed and rises again.

So, the Old Testament was written in Hebrew, and was really for Jews, although some other people. (not many), converted to live like Jews because they recognised that Yahweh|God really is the only true god.
The new covenant isn’t restricted to Jews at all, so even though it was mostly written by Jews, the New Testament was written in Greek, the “universal language” of the time. (Kind of like how English is the universal language in most countries now).

We have copies of the Old Testament writings that go back more than 2,000 years. The famous “Dead Sea Scrolls” which were discovered in a cave in the 1940’s are older than that and they prove that the copies we have of those documents haven’t been modified for over 2,000 years. So we can be confident that what we have is what was really written in the first place.

There are thousands of copies of the New Testament writings dating back to the 100’s AD. So not quite originals. We do know it hasn’t been changed since then, except for little bits here and there which could have just been copying mistakes. Either way, none of the slightly different copies of each document changes what it was about, and what it’s message is.

By the 300’s AD there were lots of documents floating around from the new covenant era. Some of them were clearly fake, some were clearly genuine. So the Christian leaders of the time decided between them which were which and made it “official” which ones were “The Bible”.
It’s possible that they failed to include something that was genuine. But they almost certainly didn’t include anything that wasn’t.

So, there we have it. 66 documents, written by 40 people, over 1600 years. In Hebrew and Greek. We have thousands of ancient copies which have only changed in minor, trivial ways as they have been copied over the last 2,000 years.

But is it true? Obviously I think it is. You will have to decide for yourself. I would suggest you start by reading something like the book of Luke in the New Testament. Loukas (Luke) was a non-Jewish doctor and historian who lived in the first century AD. He collected information from the eye witnesses to Yeshua’s life and collated them together into the document we call “Luke”. He also documented the early years of the church and how Christianity spread from just Jews in Jerusalem to thousands of people across the “known world”. We call that document “Acts”.
Read them. See if you think they’re true.