Possible? I’m sure some school would let you. Advisable? It’s doubtful an accredited university would allow someone with a middle school-level education to take a college-level course, and non-accredited college credits are worthless. If you did take a college class online, you’d almost certainly do poorly or fail it with your current level of education – making it a waste of time, money, and possibly reflecting badly on your future college work, as most universities require you to submit ALL previous transcripts, including those from colleges you failed out of.