I am glad that he does not tell you he is angry with you or anything like that. Keep in mind that being sexually experienced does not mean the same thing as knowing a lot about sex. Some people have a lot of sex without really knowing much about it. Just having sex does not mean that you know about human anatomy, birth control, fertility, or pregnancy, you know what I mean? So while you do want to communicate with him, keep in mind that he might not know everything. Also keep in mind that women are different. What worked for his partners might not be what works for you.
There's no one magical position that will do it for you. People are a bit different and like things stimulated a bit different, so they tend to like different positions for different reasons. You'll have to experiment and see what works for you guys.
Masturbation might help you to learn a bit about your body and what feels good to you, but only if you're comfortable doing it. There's nothing wrong with masturbating, but there's also nothing wrong with not masturbating.