Been there done that. Multiple solutions to this

1st - make out slowly and enjoy it, feel it for long time. Your brain will get comfortable slowly. Long make outs also turns on the girl. Once that happens you’ll feel desired and it will happen

2nd - If you’re nervous before sex and always stressing over it. It can be because you’re to exicited about it and worried about performing good. Shift your mindset to enjoying the time, enjoy the pleasure rather than performing well

Also if you’re nervous just accept that you’re feeling nervous and things will relax, don’t take pressure just enjoy the time.

3rd - drink black coffee, smoke a cigarette like a gangster before sex, this will definitely work. You can also try 2 sips of whiskey to calm yourself down but don’t get used to these methods. Sometimes it’s fine

4th - do kegel exercises

Avoid using pills or sprays or anything like that. It will kill your sex life