How to be less nervous leading up to sex

i have terrible anxiety and i get so nervous right before i’m about to do forplay or have sex, once i’m actually doing the sex or foreplay i’m usually fine it’s just getting out of my head beforehand that i have an issue with. i’m also so nervous to make the first move and i think that comes from my “””fear””” (used loosely) of rejection. how do i over come this? most of the time the anxiety is crippling 😩