*Long Post* Wanting to try something new. TKD or Karate?

Hello! I'm a 25 yr old female wanting to find a new hobby that helps me lose weight and stay in shape. I've been quite depressed lately for various reasons and am unable to practice my old hobbies like guitar where I currently live so it's like my only activity is media consumption and that makes me feel pretty useless.

For more context: I have had health issues very recently like TMD, pulling my chest muscles which warranted an ER visit since I wasn't sure what was happening and I couldn't breathe well, just feeling more weak all around in general and my recent blood tests didn't look great either. I am also anemic. It's like I'm suddenly more prone to all these issues which I never was before. I'm also not really overweight, I weigh about 160 right now (and losing weight bc TMD is stopping me from eating most food) and am 5'4" but I still don't look how I want. Though these problems may not all be directly related I wanna do something to make myself feel better and put focus on instead of worrying about impending doom/injury.

I've been pretty sedentary since graduating high school in 2017 where I did lacrosse for 3 years, mostly because I have really bad knees/joints and have for the last 10 years so activities like running are hard and lacrosse made it inevitably worse (we didn't have a real field so it was just hilly and uneven grass - at least 3 other girls on my team tore their ACLs or achilles while I was there). I sprained my ACL, MCL and meniscus in one of my knees but didn't get it looked at for about a month because my mother didn't believe anything was wrong so she refused to take me to the doctor until my coach said I couldn't play in games until I got looked at bc I couldn't even bend my leg. I had an MRI which my mother never shared the full results of with me either so who knows what crucial time sensitive info I missed. It's also been mentioned to me that premature babies such as myself are prone to more joint issues in life but I don't know if that's my case. That being said, I definitely believe my knee didn't heal properly and this is a huge part of why I struggle so much now. Nothing major has happened to my other knee but that one is super weak too at this point and I have a hard time doing things like bending down, jumping and walking up stairs. And more recently, I've gotten a new job that is me sitting at a desk 95% of the time which at first was nice since my other jobs didn't allow me to sit at all but now I feel even more guilty about being inactive and my mental health is getting worse because of it.

Obviously all of this makes regular workouts intimidating for me because I know I am very physically limited and am scared of more health issues arising heart/chest wise so I'm afraid to push myself. I also just hate the idea of "going for a run" or doing basic weight workouts anyway and want something that forces me to regularly exercise in a "fun" way that isn't also ruined by the weather since I live in a state that has horribly cold falls and winters and hate the idea of going to a packed gym of sweaty people and equipment touched by 5283737 others. I am sort of struggling with money right now too so having to pay $200 a month for a class I might not even like sounds like a big deal but I also have some confidence my mother would help me out since she's always telling me to "stop being lazy". Then again she and the rest of my family also laughed out loud at me when I mentioned wanting to do a form of martial arts a few months ago..

My boyfriend did taekwondo for about 15 years so I was initially interested in that but I feel like I wouldn't be able to do most of the kicks required because of my knees so it doesn't feel very useful to me, though he assured me any teacher would take this into consideration and I could still do other things without too much pressure on my legs. He's even shown me some basics of it but mentally I'd feel like I was wasting my time because if I can't do it right why do it at all? I wanna do the fancy kicks like everyone else! On the other hand, I have read that karate is way less focused on the legs and still gives a full body workout which is ideal for me. I also considered BJJ but I don't think that would give me the results I want.

All things considered, what do you guys believe would be best for me to pursue when I have the means and confidence to do so? Sorry for spilling my guts, I just have a lot of thoughts these days and wanted to explain my situation since it's rather unique for someone my age.