Who is the blonde girl from diary of a wimpy kid movie?

You're likely thinking of Chloe Moretz, who played Angie Steadman in the "Diary of a Wimpy Kid" movie series. She appears in the first two movies, "Diary of a Wimpy Kid" (2010) and "Diary of a Wimpy Kid: Rodrick Rules" (2011).

Angie is a popular girl in Greg Heffley's class and is initially portrayed as being somewhat snobbish and mean. However, she later becomes a friend to Greg's sister, Rowley, and develops a crush on Greg.