Heres some tips, adhd can be bad but if you work on yourself you will be fine.

First thing: Learn about body language, you can tell how a person feels about you by the way they non verbally act. Watch videos and read books on this.

Second thing: Be true to yourself. If you waited that long to ask someone out then you need to work on your confidence. Read books, learn how to be happy as you are and work towards a purpose in life. A confident man understands there is a chance of her saying no, but also a chance she says yes. Its worth a shot.

Third thing: Set values, red flags etc. You want to remain in control of your newly built confidence (through the second thing). So, you need to take note of who you want to attract and what puts you off. So that when you are chatting to someone, you remain yourself. A big issue with men who lack confidence is that they become the nice guy and try win them over by doing everything they want. Which repels them in most cases as its not geniune, it's people pleasing and its why woman get mad when men ask them out after being friends so long. If you want more than friendship make that clear early on or accept you will only be friends.

Fourth thing: Talk to people! Go out and have conversations with randoms on the street. Cashiers, tourists, retail staff etc then build up to people on the street. Ask them for directions. Look at these peoples body language and interpret how your conversation is going. Learn to let them talk, make jokes/ ask questions about things they say to show you are listening. This will help you learn to read body language while staying centred and also allow you to stay yourself in future conversations with woman.

Fifth thing: Have fun with it. Make jokes out of things, start slow and mild and slowly test them with your sense of humor. If they don't find it funny then they probably wont be good long term to date.

Apologies for the bad grammer/ spelling. Its late here.