i dont agree with this advice. if hes a friend of yours be there for him. who cares if you get involved? maybe the situation has gotten so bad because no one else has gotten involved. if needs a house to sleep in, offer yours. if he needs food, feed him. i mean hes a human being for christs sake, imagine if you were in his situation, wouldnt you love for someone to be there for you.
get involved. call him, see if he needs help. tell your parents about it if your too scared, you cannot keep this to yourself. if your too young to do anything, tell your parents, they are more mature, and will kno which steps to take to help him out.