So sorry you're feeling so lonely.
It will take a huge amount of effort and may take you way out of your comfort zone, but there are ways to make friends in life, regardless of age or looks (and I'm going to hazard guess you don't look half as bad as you think you do).
Firstly, I'd visit your GP and start the process of trying to get a diagnosis for your suspected autism.
I would also start thinking about all the things you would like to do in your spare time, new things you'd like to try and start researching these and what might be available in your local area.
I'm also a huge advocate for some kind of exercise or physical activity on a regular basis. Even if its wearing your headphones, listening to your favourite music, book, podcast and going for a walk. It's great for clearing your mind, thinking things through, your mental and emotional health - and physically too, of course.
Every week set yourself a task - maybe strike up a conversation with a work colleague, even if it's only about something you've watched on TV, smile at someone you walk past, talk about the weather with the person in the shop queue with you. These tiny changes may help build your self-confidence and each conversation may grow over time.
I hope things improve for you over time and you build some beautiful friendships which include lots of hugs, OP 🌷