can I move out at 18 and never speak to my family again?

before you read this I'm not a child who moving out for a stupid reason. I want to move out because of many reasons but the most recent one is my brother threatened me and my mother did nothing but watch which she then blamed me for making him angry when I did nothing. he came in my room screaming to give my phone. I am literally scared to live in this house and want to move out so I was wondering if I can move out at 18 and never speak to them and not have the police looking for me if I leave a note as in why I left. all my life I've been blamed for everything, treated like a slave and been hit so many times but yet I would do anything for them but this is the last straw I want to move out and have them not look for me. I want to move forward in life with my boyfriend and forget the 18 years of hell. I live in the UK and please don't think I'm just being a immature, there is so much a person can take and honestly I can't take it anymore. any advice would be helpful thank you in advance x