Once you understand how God relates to time the free-will/predestination conflict goes away. Being outside of time altogether, God can look at any point along the time line whenever He desires. Before He created Earth He was able to see every person ever born and knew whether they would choose the remedy He provided for their sins or not. Thus He foreknew every believer. Those He foreknew He also predestined, which simply means He made a non cancellable reservation for them in His kingdom (Romans 8:29). At that time their names were written in the Lamb’s Book of Life and cannot be blotted out.
Within the time domain every believer makes a free will decision to accept the Lord’s pardon. Outside the time domain God knew we would and had already reserved a place for us in His kingdom. If this was not the case, verses like Matt. 7:7-8, John 3:16, and Romans 10:13 could not be in the Bible