The overall vibes is very similar, the main character narrated throughout the drama. Both drama has a story where teenager dealing with unfortunate events and involved in crimes then regreting what they've done. Both drama also highlights on bullying that can't be seperated when it comes to korean high-school drama.
Here's My Plan has a similar tough and assertive FL . You don't always approve of the FL's actions in either show but you slowly understand why they are the way they are and keep everyone at a distance. Similar dynamics, but Here's My Plan has more slice of life vibes while IOTNBO has more fantasy/melo vibes.