In Japan Do You get To choose your classes in school?

Question:

having thoughts about going to japan in last year of high school, and if i do go to a high school there i wouldn't wanna attend to any class other then japanese language class, my sister who studied in china only studied chinese language and graduated so that should be possible in japan too right?

Answer:

All classes like math, history are in Japanese at a Japanese high school.

You are supposed to finish learning Japanese, like 2000 kanji, before joining a high school. And you will learn more advanced Japanese at high school.

So the answer is NO. You can't finish a high school only with Japanese classes.

There are some electives. But many classes, like math, history, are compulsory.