>>86136 (OP)You can't do much about it as is, you have to tough it out until you can move out
Spend way more time outside. If you're burnt out with college, it might help to do college work in a library, and otherwise just walk around 'n shieet. Maybe grab a cheap bike/skateboard and fuck around with that outside. Doing sports increases your self-confidence, makes you more fit so he might not be able to push you around as much, and also you won't be at home so the bastard cunt won't be able to bother you as much.
Next time your stepfather tries to push you around, fucking body check him by slamming your shoulder into his. This only works if you aren't a short frail dude, but if you aren't it shows him you aren't just going to take it. He will still verbally be annoying but if you make it clear you won't go down without a fight, most people give up on violence