Hi there -- not to discourage more answers, but "world's oldest university" questions are pretty popular here. You may want to check out this answer from u/cptbuck about what "oldest university" means:

https://www.reddit.com/r/AskHistorians/comments/4idy6k/what_are_the_oldest_universities_in_the_world/

or this section of our FAQ on formal education and universities: https://www.reddit.com/r/AskHistorians/wiki/dailylife#wiki_formal_education_and_universities