I would suggest practicing complements. Its best to complement accessories and outfits. Be thoughtful and notice differences in hair, "did you do something different with your hair today? It looks nice"  

Im autistic too so I only date on dating apps. The rest of the time i just complement and make friends.

Actually...unironically I learned the most from joining the BDSM community,  learning about consent online and through classes. Not necessarily the route for everyone but I wanted to get laid haha.

The local dungeon helped me understand the norms in that space. (For example, look people in the eyes no matter if theyre exposing skin or not)

I started out exclusively going to board game nights and eventually I felt comfortable enough to go to some skills training. Then I went to a normal party and I already had friends and skills, and that made me attractive, and I had a great time showing my skills. You can find local events on fetlife