how do i masturbate...

i’m 14 and it’s so hard to get pleasure i literally can’t even feel anything only for like a couple seconds then it goes away. i don’t have a lock on my door so i can’t touch myself when i’m not in the bathroom. i get so horny and it’s upsetting. if i had someone else try and pleasure me would it be better? i’ve heard of so many ways but i can’t do them because i get no privacy and i’m in high school lol. i’ve asked around and i still can’t get the hang of it. please help

edit: one thing i should have mentioned is when i was little i had surgery on my vagina because i was born with it closed and i couldn’t urinate write so they had to do surgery and open it and ever since i’ve been able to urinate right. i’m sure if this affects my sex life.