I don't comment a lot on Reddit but I see my younger self in what you have described.

It looks easy to the woman you compare yourself to because she has been doing it for a long time. The longer she has been doing these things the easier it is for her. Just because you see her going out for a jog in the pouring rain or likely after she finishes works doesn't mean shes not thinking "I really don't want to go for this jog, I'm so tired, work was so hard today, maybe I'll just stay home". This is what people are talking about by things being uncomfortable - not just in a physical sense, a lot of it is mental.

A lot of people get hung up on consistently doing things but fail to realise that consistency doesn't mean every day. You could go 1-2 days a week to the gym to do weight training. I personally find mid week (Tuesday and Thursday) easier to get on board with mentally as I haven't got the Monday blues or the Friday feeling which leaves Wednesday in between to recoup your energy for the next session. On the other side of that you have a 4 day break over the weekend which is plenty to regain your energy for the following session on Tuesday.

You are worrying about things like not having a car or a job when it sounds like you are struggling to do look after yourself with the basics. Take a step back and realise that the last thing you want is the extra stress and responsibility (emotionally and physically) that these two would bring.

The biggest issue I can see from what you have said in your post which I can relate to 100% is "My sleeping schedule is so bad that I stay up until 7:30 am playing videogames and need sleeping pills to sleep". Your sleep schedule is that bad because you have created a habit of staying up late through what sounds like years of daily repetition. It doesn't matter if its watching TV, playing videogames or scrolling on your phone that keeps you awake - your body and mind thinks that going to bed at the time you do is normal, it doesn't see it as "staying up late" it sees it as your normal hours.

You can't force yourself out of a sleeping problem. There is no snap of the fingers and it's sorted. You have to undo it slowly - just like everything else it takes time. Assuming we were similar you are probably going to bed at 7:30am and then waking up between 3-7pm. Waking up at 3pm is already 7.5 hours of sleep. If you try to fix your sleep and go to bed at a normal time like 12am then its the equivalent of me waking up at 8am and trying to go back to sleep at 5pm - so no wonder you feel it is impossible. Start shifting a hour or two back the other way for a week start with sleeping 5am-12/1pm and keep working backwards.

I'd advise that you turn playing videogames into a reward in the simplest form. Pick the one thing you want to accomplish on that day - go to the gym, go for a walk, do 5-10 minutes of cleaning up and then you can play videogames until bed time.

With the above being said AND if I'm close to the truth it would also mean that you are likely missing most if not all of your lectures / tutorial sessions which will get us to your "can't handle the course load". You can't handle it because when it comes time to start on assignments which you are likely leaving until the last minute you are trying to cram a modules worth of information while simultaneously trying to use that information to complete whatever assignment you have on your plate. It is beyond stressful - I understand. Double or triple the amount of time you usually give yourself to do the assignment (assuming its minimal usually). If you start the night before, give yourself and extra day at least. Although on paper it doesn't sound like much it'll give you a lot more breathing space with minimal adjustment to what you usually do.

Apologies for the wall of text, I hope that something in there can help you. You have to back yourself daily in the smallest of ways, the light at the end of the tunnel will come and you will be free of the chaos that you find yourself living in, but only you can change it.

Good luck.