If noise from outside is an issue, then I'd highly recommend investing in a white noise machine. Personally, I've found such a device to be absolutely invaluable to my sanity. Noise still gets through to some extent which can, at times, still greatly annoy me, even with the benefit of white noise, but it's better than nothing and, more often than not, helps to drown out the occasional racket my parents make from outside my door/room. I use a dedicated machine I bought online, which comes with multiple tones & variations to choose from, but you could also use a fan (not very practical in winter, though), or some app via a phone, if you happen to have one. Which I don't have, since I don't go anywhere and have no one to call, and anything else I just use my computer for. I guess you could also use your computer to play white noise, but a separate dedicated machine you can move around is, in my opinion, more convenient.
As an aside, I really wish I could soundproof my room further, but I'm just not sure how to go about it. I have a heavy curtain that hangs in front my door that I can pull across, but the sound dampening is minimal at best. I also have an attached door sweep, but, again, it doesn't do much. I'd need a way thicker door and a tighter seal around the frame to make any real difference. I'd need my parent's involvement to replace it though, and I just don't have the energy to make the necessary fuss.
If light from outside peeking through your curtains is an issue, try finding some objects to help lean up against the curtains to tamp down the edges. I have a shoji screen and a picture frame keeping both sides of my curtains down on the main window and it, mostly, keeps the light to a minimum. On my side window I just used a combination of tape, staples & bull clips to keep the light out and the curtains flat against the wall. If light from the top is an issue, try stuffing a blanket or towel up there in such a way to keep the light from bleeding through. It's not pretty, but, in my case, it works. I actually swapped out the blanket for a long piece of cardboard that I was able to throw up there and it, more or less, accomplishes the same thing. At least with the cardboard, you can still open up the curtains at night, assuming you want to crack a window for a bit. If the cardboard falls off or is bending up, try taping it down to the curtain bar.
In my case, I could probably do with taking some Vitamin D supplements (I have a bottle of them on the coffee table next to my pull out bed, actually), but I can never remember to take them. I really should though, since I know it's important and could very well improve my mood/overall health. Taking pro-biotics everyday did wonders for improving my digestion.
Exercise wise, getting a workout mat & a basic set of kettlebells can be a good starting point. Every few days, I do 6 sets of 10 kettlebell swings with a 36 pound bell, 10 Turkish get-ups, one for each side, with a 15 pound bell, 3 sets of 10 sit ups, 3 sets of 10 rear leg raises, one for each leg, 3 sets of 10 bicep curls, one for each side, with a 15 pound bell, and finally 3 sets of 10 goblet squats with that same 15 pound bell. It's not much, obviously, but it's something. Even if it's a futile gesture in the end, it helps to break up the days. I'd like to exercise more intensely, but I'm trying not to push it for now.
I use a Wahl Peanut for shaving, which I find to be very effective & quick, and a sonicare toothbrush which, quite literally, makes me feel like I just came back from the dentist whenever I use it. Chewing Xylitol gum after every meal can also help a good deal in maintaining oral health, assuming you have issues there. Personally, I just like chewing gum and, in a small way, it's saved from me from having to suffer any problems with my gums/teeth. I also happen to have long hair, which I'd strongly advise against, since it's a total fucking hassle with very little benefit, especially given the fact that I never go anywhere. If it weren't for me looking like an idiot with short hair, along with my mother helping me brush/dry it, then I would've shaved it all off long ago.