It's easy. Simple as that. Honestly it doesn't matter what you do. Just stay in your lane. Grades are easy for the most part, and teachers are usually chill.
If you meet a weak minded person who likes starting fights, just back down. It's not worth your time.
Also, high school friends are mostly temporary. You'll most likely never see some of them again after you graduate so that's that.
Use prefixes, or suffixes , as well as any visual aids around the text you are reading. Most words have roots in either Latin or Greek, so finding the root of the word will help you figure it out.