That may be true for Luke, but Paul was likely well acquainted with Jesus and His teachings.
Paul was a pharisee, and an adult, and in Jerusalem at the time the persecution of the church broke out. there is every likelihood that he encountered Jesus while Jesus was going through Israel teaching and healing.
You stated as if a fact that Paul was never present for any of his teaching.
Prove it.
Prove he was. It us generally known that he never met him.