how to satisfy a girl

Depends what you mean by satisfying? Make her have an orgasm?
If the answer is yes, know that the female orgasm is different from the male one. Sometimes women don't come but it's not necessarily your fault, it's 50% and 50%. Forget all that bullshit about dick size, movement during sex etc ... the woman cums in her head! if he has emotional involvement, rest assured he will come.