Answer:
The ""you"" in line one of stanza three means he is addressing humanity at large.
Step-by-step explanation:
In the first line of the third stanza, the writer ponders about who he is, and also writes about how it can be difficult or hard to understand the truths about one own self.
This is a universal feeling for humankind that most of us have to deal with; when he says "you" here, it means he is addressing humanity at large.
In line 30, he as well addresses the instructor directly with "you", which is clarified by his wording "it will be a part of you, instructor."