How do you get Donald and goofy in Kingdom Hearts

It all depends on how far you are. If you have already left Destiny Islands, and have ended up in Traverse Town, then it's going to be a huge maze game with Donald and Goofy. While you're entering one place, they exit out of one until finally by chance you meet up. Sadly there's no way around this, and you'll have to just go exploring around until you meet up in the 3rd district I believe where there's a cutscene, and all of you beat this huge Heartless. Best of luck, and God bless.