ANSWER:
He must come out of the closet and be proud of his Islam. You are obliged to obey your parents unless they make you disobey Allah the Almighty. He should tell them that he is a Muslim so that he can openly practice Islam. He should go to the Muslim center and announce his Islam officially and trust Allah. It won’t be easy but Allah will be with him. Hiding your Islam is not permissible unless there is a real threat to your life and safety. If there is such a real threat, he must leave his family and move out with a trusted Muslim family until he can get financially independent of them.