I think I would start by asking your professor why a second person opening is wrong in his/her eyes. It is possible that your professor prefers the more academic approach to writing, which means you need to put everything in the third person to get the grade you want. Using the second person is less formal, and it is the only reason I can think of for not using it as you described. At the same time, it’s all about a grade and not really about using English to its best advantage. So while I say you can do it, don’t if your professor prefers the more literary approach.