What did the main character learn in end of diary a wimpy kid?

At the end of "Diary of a Wimpy Kid," Greg Heffley learns the importance of genuine friendship and the value of his family, even if he doesn't always show it. His schemes and attempts to become popular ultimately fail, and he realizes that his relationships with Rowley and his family are more valuable than superficial popularity. He begins to appreciate the good things he has, even if it's not exactly how he initially planned it.