TMI !!!!!!!! How to make my boyfriend.... Yu know

Soo . me n my nf have been having sex for ab 2 weeks now . i have never made him cum and i feel really self conscience about it . like am i ugly or too big? Am i not doing it right? How do you do it right? Im so confused lol plz comment n let me know . he always wants me on top because he has no idea what hes doin.. ik this is weird buh yeah needing sum help. So plz comment n dont judge mee.