While it is a very sensitive topic which requires maturity to be able to debate it is still one that needs to be understood so you have guts that is for sure
To be honest I have never found enough evidence for what I believe vs what the opposite can search up in the scriptures.
If you go to google you can easily find evidence for both sides free will vs predestination but here is my take on it.
We can find the evidence for our position but if we fail to take into consideration who God is and his pattern of doing things we can miss the mark.
God has all throughout the bible sent a warning before he does anything even in Noahs age he warned noah and Noah in turn warned the people, even though they didn't listen he still tried why is that?
Every time the Jews ran from God he always sent them a prophet to warn them to change their ways, even when Jesus came into the scene many would not accept his ways yet he still spoke to them and tried to teach them.
If in fact every person was born destined for heaven or hell then warning and trying to get them to change their ways is useless but God always did anyways. Not to mention the most obvious factor in that he is love and is the father. If you were a parent would you have children and decide which one was going to heaven or hell no matter what they chose in their decisions? Would you take the time to create them raise them and try to teach them if you already decided they were going to a final destination?
In my opinion the names in the book were never set in stone they names were added when one chose to accept him. Remember that salvation is called a gift and is never forced on us there is a good reason for that.