hello this is a common problem..firstly you need to explore your own body first and find out what you enjoy most..once mastered the art of what pleases you then you teach your partner..
foreplay can have a huge affect on how you enjoy sexual pleasure and makes it more fun finding out what ways can bring you to an orgasm..
if you just jump in its not the same as its an art and pleasure to be enjoyed by both.
most importantly relax. you shall find this important time in your life where you seek satisfaction shall begin to come to life.