I will speak as the parent of a junior (who is not on CC).
When was the cutoff for dropping? If it was within a week or so, you might have a shot with getting your parents involved. At my daughter’s school you have three weeks. I personally would have no problem getting involved if it was important, but do not delay. Have you reached out to the teacher at all?
There are many resources in this forum on APUSH help. You can probably find sample essays online, or have someone read your essays for feedback. I will say, sadly, don’t necessarily rely on a teacher to teach. My daughter has a (regular) history teacher who quizzes on the chapter before he teaches it, and until she figured that out she was not doing well. She ended up taking her own notes and not relying on him - and, with my help, her notes are far better than anything she gets in class. I understand some APUSH classes are run somewhat the same, but I have no personal knowledge.
My daughter is not taking APUSH because I always felt it was way too much work for questionable gain - and I say that as someone with a history degree from a very good university who did just fine without anything resembling APUSH in high school. I won’t go into the many reasons I feel that way.
It’s now up to you to figure out if the class is worth fighting to stay in or get out of. Good luck.