Professors of computer science arent always the best people to take business advice from.

First question to ask is do you want to make a business from your project? if so, then you really need to worry about IP rights, which are commonly given to the university if I am not mistaken.

Assuming you do want to make a business and IP issues can be worked around, then you can begin to question whether open source is best or not. Without knowing more about the project its impossible to give any suggestion either way, all I can say is being open source does not mean you cannot build a business by any means, a lot of people conflate open source = no money but that is not at all true.