ive been there before an asshole stepdad and no drugs i know it sucks dick but you dont even live with your mum any more and you said your grandma is cool theres tons of ways to get money you just have to be creative like saying your going to the shops and get like a £5 or £10 then you just head down and buy someweed or whatever you want and like you said you know alot of dealers and your going to be going to your dads work soon so just tick them and give them the money when you get it or tell your dad you need money because its summer nd your bored dont steal the money though that just gets you into more problems