Hey!
No, it is not usually essential to stay in hostels facilitated by Colleges and Universities. Many students make their arrangements and stay outside of college hostels. They usually get a separate pass alloted by college than the students who stay on the campus. If you want to know about any specific Institution's norms and rules regarding the hostel facilities, then you may mention it in the comment section so that an answer pertaining to that particular Institution can be provided.
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