How can i disown my father (am 15)

I have an abusive father. Extremely abusive. He's always angry with me for no reason. My brother and mum don't provide me any relief, on the contrary; my brother is a pain. I REALLY wanna stay away from him. I even clicked photo of one of my wound though that thought came to me hours later hence most got healed. Both my parents are partial to me and always support my brother. It is as if am adopted or a bastard. They don't try to understand my feelings. This has been going on for the past few months. Their first excuse was that this was lockdown and dad is getting frustrated. Then they told that he doesn't have a job hence his behaviour. Now my dad has a job and they are out of excuses, and i am out of options apart from getting rid of him. I don't want to file any case against him(if possible) because he's the breadwinner of our family and my mum and brother will be on road. The other worry is that if i move out i will get no financial help. I used to think that he might feel pity and give some money, but that thought went over my mind when he was going to hit me with a hard metal rod. Am a person who doesn't like to ask even for the cheapest thing. But this time. I REALLY NEED HELP.