You must first understand that sin is the work of man alone.
We are free, and must be if expected to not feel as if slaves or prisoners. Our freedom is the Will of GOD that we might come into faithfulness with HIM out of genuine desire to do HIS Will. Though sin is of the hands of man and GOD created man. If we had been created without freedom then we would not be capable of loving GOD out of reciprocation of the love that GOD shows creation. The root of evil is greed. Is GOD greedy for giving us both freedom and mercy and grace.
I am not denying free will.
If you are saying that God knows everything that we will do before we were created, then we cannot have free will, because it is already written. You can't have your cake and eat it too.