Najlepsza Odpowiedź!
I read your letter and I will try to help you.
If you want to stay late away from home and parents don't want to let you, they probably have a reason. They certainly are afraid of you. You need to prove them thet you are responsible. Back home always in particular time is important. You can ask a parent to let you stay for longer but you have to keep it. They will have confidence in you and they will let you stay out late.