Allie, we can tell you are immature b/c of the questions you are asking. Someone who was mature would ask different ones.
You're not going to like this response, I know. And, no, I'm not going to tell you what I *think* you should be asking; b/c that particular realization needs to come from within you.
Your BF has his priorities exactly right. And if he is concerned you aren't good for his daughter, tough. You should be pleased he is so responsible.
Imagine that this man is trying to decide, if he were to marry you, whether you would be the person he would want to be responsible for his daughter's welfare if, god forbid, something were to happen to him. That's what you are considering signing up for, btw, not just some blissful marriage fantasy.
Think about it.
Second thoughts can generally be amended with judicious action; injudicious actions can seldom be recovered with second thoughts.
--Cyteen by C.J.Cherryh