Homeschooling, Middle school Science, ELA, and Social Studies Curriculum order questions

I know khan academy's math curriculum is amazing. I experienced it myself, as a 7th and 8th grader. But I recently turned to homeschool and I really need some help and tips. Especially since I can't get them from my parents(they don't understand enough English to help me). I really really need some help right now... If anyone sees this, please answer

My question is about if you can use only Khan Academy for Homeschooling.

Are the ELA courses enough?

Which Arts&Humanities course is for 7th grade?

Between the 3 new courses in science, which course is for which grade?

Are Khan Academy's courses aligned with homeschooling core curriculum standards?