Living with a bad-tempered brother. Should I move out of the house?

Who owns the house and who is paying the bills? I know rudeness and bad temper is not an excuse but who stays and moves out of the house depends on who owns and pays the rent, if you are both living with your parents then you can bring this up to your parents and they can confront your brother about his behavior, if your brother owns and pays the bills in the house then unfortunately he can technically do what he wants and you can move out and start being independent since you are 21 and live peacefully on your own or get a roommate to help you pay rent.