I am a 25 and virgin. i never retracted foreskin before. now when i have sex my foreskin is retracted. when its not retracted, i have a hard erection for more than 20 mins but i cannot get any erection when it's retracted. what should i do?

You cant be a virgin and say you have sex at the same time. Keep foreskin forward if retracted position causes problem.

You may have narrowing of the foreskin. It would be prudent to see a doctor to ascertain if circumcision may be needed. Get HPV, Flu and Covid vaccines. Wish you good health! Safe sex: https://www.hopkinsmedicine.org/health/wellness-and-prevention/safer-sex-guidelines