Privacy issues with dad?

First off im 10 years old (yes i know very young) anywayss the issue is privacy because mainly my nosy dad just barges in and irritates me so i want a lock on my door for more privacy since i deserve it.My mom promised me if i kept my room clean(we moved it downstairs so when people come over it has to be clean)she would get me a lock meaning next month and this month seems to go by so slow since im anxious for my lock :).A few minutes ago my dad yelled at me for having a slight attitude and i put a chair under my door and get got a hissy fit because if i put the chair under he cant get in.GOD I HATE HIM SO MUCH anyways how to keep him out my room with his nosy self.I know it sounds like a rant but its not i mean every teen-preteen needs some dang privacy so how i keep him out my room my mom agrees with him but when hes not around she is my best friend and she wants to talk crap but in front of him she makes him feel superior but he not he just makes himself scary when he's not :) so please no bad comment this is serious i need privacy whos with me?oh and by the way he has serious issues like controlling :( so yea um tell me who's right and how to keep him out my room srry this so long