What does Millicent learn from her experiences in initiation week?

The thing that Millicent learn from her experiences in initiation week is: She does not have to join a club to relate to other people.

Millicent went through the initiation because she was desperate to be accepted as a part of the popular students so she could get acknowledgment by other people. But, after the initiation, she realized that she simply just need to be herself in order to connect with other people.