Self imposed exposure therapy my man. Start very small. The goal here is to have as many socially positive/neutral experiences as you can to build your social and speech confidence. A simple smile to someone walking the opposite direction as you could be a start. Do that to the point where it no longer becomes an issue and then add in a “hi” or “hello” with your greeting as the next step. Do that until you feel like it’s second nature and graduate to more elaborate stuff. Always remember, confidence comes from *doing*. I hope you get to live the life you want for yourself.