The apostle Paul gives it to us straight:
In the past I spoke against Christ and persecuted him and did all kinds of things to hurt him. But God showed me mercy, because I did not know what I was doing. I did not believe.
But the grace of our Lord was fully given to me, and with that grace came faith and love that are Christ Jesus. What I say is true, and you should fully accept it: Christ Jesus came into the world to save sinners, of who I am the worst. But I was given mercy so that in me, the worst of all sinners, Christ Jesus could show that he has patience without limit. (1 Tim 13-16)
Read Romans, read Galatians, read Ephesians, read Corinthians… Matthew, Mark, Luke, John. Read where you feel called to read. It’s all there. Read the Bible.