If the Bible were simply a book of human philosophy or a collection of myths and fables from long ago that had no basis in fact -- then there wouldn't be any reason to trust its teachings or base our lives on them. But the Bible isn't like this. The Bible tells us about God -- and one of the most important truths it tells us is that He wants us to know Him.
Think about this on a human level. How do you come to know anyone -- even casually? If they stay hidden and refuse to have any contact with anyone, you'll never come to know them; you may not even believe they exist. But if they reveal themselves to you -- both by their actions and their words -- then you'll get to know them; you may even become their friend.
The same is true with God (although in a much deeper way). God wants us to know Him, and He has revealed Himself to us -- both by His actions and His words. And the Bible tells us about this through the human authors who recorded them -- many of which they witnessed. The Apostle Peter wrote, "We did not follow cleverly invented stories when we told you about the power and coming of our Lord Jesus Christ, but we were eyewitnesses of his majesty" (2 Peter 1:16).
I trust the Bible for many reasons -- from archaeological discoveries, to Jesus' own attitude toward it. Don't let doubt or anything else keep you from the Bible, but ask God to speak to you as you read it with an open heart and mind -- and He will.