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

Obviously by your comment, you don't feel safe with him. That is not a way to live, especially if he is your own brother. Why do you share a room with him? Do you pay rent? Safety would be more important to me than believing that you may be homeless. If he is so bad tempered, he might do something bad to you. If you are 21, you should have a job, perhaps you can move in with a friend or share a room with someone you trust not with someone that's going to make you loose sleep!