I teach APCSA along with other courses. Self studying may not be as hard as some other subjects if you have the right kind of prior knowledge. The disadvantage is that you may not have access to the materials in AP classroom. The FRQ training there is highly beneficial. If you really want to self study, I suggest that you contact the APCSA teacher at your school.
Every year I have students asking me for resources to self study for APCSA. I give them everything. However, half of them give up by Halloween, and the other half by winter break. The only exception was during that remote year.
It is doable, more so if you have a teacher you can go to with questions, and you set up regular checkpoints. Good luck.