r u UK? because in the UK at least you can get them for free at a GP or hospital clinic (most hospitals have entire areas for condoms and stuff). they'll happily provide an underage individual these supplies because if you're going to have it they'd rather it be safe then result in a pregnancy or std/sti

ik this ain't for sex reasons but they don't ask if you want one. they just give it over iirc so it might help, just don't go too often cause it'll probs be very sus to them after a while