You can find rayed-bqn users in the BQN forums and the raylib discord in the BQN channel.
Rayed-bqn welcomes contributors, and there are plenty of ways to help. One way is just talking about rayed-bqn in the BQN forums, pitching ideas and correcting mistakes, including spelling mistakes! If enough people pitch in, it might be time to make a rayed-bqn discord, but not neccessary yet.
Another way to help is posting issues on github, which works better for organized discussions. I might even add issues myself as a todo list.