Here's what you lack: perspective. That you say you would rather work for McDonald's than bite the bullet and get a degree that's actually worth something to society is telling. It tells me that you've never actually worked for McDonald's, at least not in the capacity where McDonald's was the only thing that stands between the roof above your head and you being homeless.
Do not make the mistake of thinking that you are going to always want to simply smoke bud and play video games - your 30-year-old self will arrive one day and beat the living shit out of you.
I feel for you, I really do. When I was your age, getting a career and a stable job was the last thing I wanted to do. I skipped college to try to become a rock star and party all the time. I won't lie; it was super fun. For the most part, I don't regret doing it. However, what is currently difficult for me is having to deal with that decision now that my priorities have changed, just as yours will if you too get the privilege of seeing what awaits you in the real world years from now if you only desire to fuck off with your time.
Being poor for a brief period of time is maybe an inconvenience at best. Being poor for an extended period of time (years and years) is no longer an inconvenience at best. It is no longer fun, in any way. It demoralizes you as a human being. I've worked some piss-poor jobs in my time. The types of jobs that break you, physically and mentally. The types of jobs that you get literally stuck in - that don't pay you nearly enough to be totally shit on, day in and day out, but you know that if you don't work 20+ hours of overtime, you won't pay your bills. You know that this is probably the best job you can get at the moment, because you don't have any other skills.
I can't force you to enjoy what you're doing, or force you to understand the value of the investment that you're currently making. Honestly, I'd recommend seeing a counselor. If I had to give you direct advice, it would be this: suck it up and finish. Get your degree. Try, as hard as you can, to find something about it you enjoy, and latch on. It's cool to be a young kid and it's a total drag to have to do this super hard math stuff or whatever when all you wanna do is control some pixel images inside of a rectangular light box while under the influence of some dank-ass kush. But you can still do that shit with a degree if you want, and then at least you'll have some actual skills and an opportunity for gainful employment because society at large doesn't really give a shit anymore about fry cook experience. Don't try to downplay the effect money will have on your future well-being. It's hip to think all you need is milk crates, ramen noodles and a TV in your studio apartment, but that shit gets old real quick.
The world is fucking huge. Just because you haven't found exactly what you want at 21 doesn't mean the world ends. Don't rob from your future self just because your current self can't get exactly what it wants.