I know that fundamentalist Christians are not going to like what I say, but if you hang in there and absorb this, you will realise that you can go right on believing, while still changing your view of the Bible, and accepting a more rational one.
The Old Testament is a wonderful LIBRARY of ancient Jewish literature of all sorts. It includes: creation mythology, legendary heroes, genealogy, history, law, poetry, old sayings, allegory (that means a fiction with symbolic meaning), erotica and prophecy.
Should we believe that all this was virtually dictated by God himself?
Can we be Christian without believing all this in a literal way?
So what is the Old Testament?
It is a TESTAMENT (i.e. written testimony).
So what does it testify?
It testifies that very many people, in very many ways were recorded as claiming that GOD had made himself known to them. Those people claim that God made himself known through Angels, through miraculous gifts of food, water, healing and guidance, that he led people with a pillar of flame or cloud, that he was heard in a still small voice. Right through the Old Testament people testify to the existence of God.
This EVIDENCE OF GOD'S PRESENCE is what the reader of the Old Testament is expected to believe, not the fanciful story that God created the universe in six days and took a rest on the seventh, or that God will give military power to those who follow him.
Once you have freed yourself from any notion that the whole book has to be taken literally, then you can start exploring the testimonies for the revelations that they contain, and start looking for God's continued revelations to people, to this day.
Does God STILL reveal his presence, in the ways that are described in the Old Testament?
Most definitely YES
You only have to start talking about this to friends, and you will find people who will say, (often cautiously, expecting to be disbelieved) that they saw, or felt, or heard the presence of Jesus at a time when they were feeling down-hearted, sick, lonely or were in trouble.
Sometimes people report dramatic experiences, like the one that the Apostle Paul had, on the road to Damascus.
These experiences sometimes happen to people with no Christian background, and no knowledge of the Bible, because they live in Saudi Arabia, or some such place where Bibles are rare or forbidden.
This phenomenon is not new, and it is also not a thing of the past.
What are the main teachings of the Bible?
Jesus summed them up:
God loves you, and has expectations of you.
You must love God, and love others as you love yourself.