I need advice on how to help my 17 year old friend

Hello I have a friend that is 17 years old she lives with her mom, sister, brother, step-dad,and step-dad son. Her mom has a lot of medical problems always takeing pills but also drinks every night her step-dad works and comes home and drinks too. My friend whats to get a job but the step-dad wont let her, she cant ever set a foot outside the house because he wont let her he has to always have is eyes on her while her sister that is 13 can go out with friends sleep over at friend houses and goes out of state with other people and she is allowed to have a phone, while my friend cant have a phone she cant go outside everyone in her house call her names they treat her very horrible. My friends mom wont even help her she takes her husbands side and her siblings treat her like ****. If you can please help me to help her please do also my number is 6128003963.