I first of all want to clarify that I believe that the scriptures are true. They are beautifully accurate historically and practically.
The stories told in the Old Testament and especially in the Torah are based on Oral tradition. The stories existed for centuries. The stories purpose was to give Israel identity, to inform them of where they'd been so that they might decide where they are going. What we have to question, every time we read it, is whether the point that was being made needed historical accuracy for it to be conveyed.
for example; the point of the person of Abraham, in the book of Genesis, is to explain the covenant between God and His people. To not only explain it's origin (Abraham) but it's nature of being passed "from generation to generation" (to Isaac and Jacob). The stories were true. An actual covenant was made to God's people and it was passed from generation to generation. With this all in mind we must ask, did it have to be a man named Abraham? Does the story have to be 100% historically accurate for it to be true? Would God be lying if it wasn't historically accurate?
The point of the Bible is that the stories are true, not weather they actually happened.
As you'll notice this opens up a whole new series of questions. And that's ok. If you read the Bible with an open heart then it'll always bring up tons of questions, possibly more questions than answers.
What you'll find, if you study history, is that there is a great majority of stories in the bible that are well verified by history and some that have very little real historical backup at this point. If history repeats itself then we will soon find explanations for the stories that can't yet be verified (like much of the book of Joshua). Abraham's described to have lived in a real place (Haran, Genesis 12.4) that we know really existed. This suggests to me that he was probably real. There are also other things that suggest his historicity which we will not discuss here. But we still have to ask the tough questions. What if there was no historical verification to scripture?
We have this beautiful concept called faith. It is one I will always base my life around. I have faith that the Bible is true. Not blind faith (I don't study for no reason) but faith indeed. And it is with faith that we approach the Bible. Faith is a non-negotiable.