Almost every kiddo I’ve worked with has trouble accepting “no” for an answer. It’s like kids are allergic to hearing “no” and the reaction? Arguing, whining, and pouting.
Luckily, any board game can be used to practice asking permission and accepting “no” for an answer. I have Don’t Break the Ice, Candyland, Chutes and Ladders, UNO, and Go Fish in my office, but really just about game where players take turns will work. How the practice works is that the kiddo must ask for permission before taking a turn. If I say “yes” (which I do about half of the time), they get to take their turn. If I say “no,” then the kiddo should say “ok” and keep their hands in their lap.
When they start to get good at it, I’ll say “no” a few times in a row, which usually leads to some frustration. At that point, I can practice calming strategies with them and provide them rationales for staying calm. If they kiddo can accept “no?” I give LOTS and LOTS of praise. If there’s any whining, arguing, or pouting? Consequence, then try again.