Amazon Mechanical Turk
You likely won't earn much until you figure it out. Even then, unless you do it full time religiously you can't live off it but it's good to get an extra couple hundred bucks a month. I used it when I was in college and got good at it. Was able to easily make $30-50 a day with about 4 hours of work, which is shit I know but when you're struggling...it helps lol
You basically complete tasks that haven't been automated yet or take surveys for research. It's very tedious but depending on your bank and how fast the requester approves your work, you could get the money the next business day.
There's forums and scripts out there that'll help you optimize your time.
You must be 18 and a US citizen/have a tax ID or SS#
Edit: the sub r/mturk would be a good place to start.