A Chinese dumpling (whether called jiaozi, 饺子, potstickers (pan-fried dumplings), or wontons (similar filling but different wrapper)) is one of my favorite Chinese dishes. I have fond memories of spending Sunday afternoons making dozens of jiaozi with my family. Every child starts off with making stegosaurus-like jiaozi, but, hopefully, these evolve into shapes that everyone recognizes.
Putting together a recipe for the filling is a bit difficult, as family recipes and individual tastes vary. Look upon the recipe as a starting point, and fiddle with the ingredients until the combination is one that you like. We tend to like lots of ginger and garlic in ours, but your mileage may vary.
And YouTube videos are perhaps the best resource to learn how to fold the dumplings.
The recipe is here: