1. what is he like? = What is his personality? May also refer to appearance, but principally personality. 2. what is he look like? Not correct. 3. what does he like? = What things does he like, like foods, sports, etc. 4. what does he look like? = What is his appearance, like hair color, height, weight, etc.

"What is he like?" - This asks about his personality. Here, 'like' is a preposition. "What is he look like" - This is incorrect, because 'look' is a verb. "What does he like?" - Here, 'like' is a verb. This asks what kinds of things he likes (ex. sports, music etc.) "What does he look like?" - This asks about his appearance. Here, 'like' is a preposition.