Question: My friend is here in visitor visa my question is can he apply for the student visa while he is here in USA?

Answer: Yes, change of status can be applied only if it meets the strict criteria laid out by the USCIS. You can not file for any change of status within 90 days from the date of entry and also has to be able to prove intent to return back to the home country by showing emotional and financial ties to the home country.