I do sympathise with the difficulty in making friends. I have very few friends, and the ones I do have quite frequently have to reassure me that they are in fact my friends and they like spending time with me, so I do understand.
I wonder who you have in your life that supports you? Professionals, parents etc? Maybe talking to them (if present) would be helpful?
The thing that helped me make friends (and this sounds silly) is the fact that I love children. So, I met one of my best friends as a result of her little boy, he loves me and constantly wants to see me etc etc and our friendship built that way. I realise this might not be possible because of social anxiety or your situation but do you have anything in your life (college, work etc) where you could start slowly by saying “morning,” or whatever to people? Not sure how practical this would be, but just a suggestion.