As someone who loves Sarah Dessen’s novels, this isn’t great. Characters are wildly different from their book versions, important events are skipped, and the key character development gets misplaced and lost.
It’s an ok movie, but don’t think that it is an accurate representation of the novel. Sarah built better characters and Auden had a much more substantial growth in the book than she does in the movie. It’s kind of like The DUFF movie, not bad, but almost nothing like the book. I would recommend reading the book though, just for a fuller picture of Auden’s world.