I have a number of recipes that call for pork. Am I able to substitute with beef? And when it calls for chicken stock, do I use beef in place?
You can almost always adapt recipes to use other meats, but, obviously, the flavors are going to be different, so it might not turn out as you expected.
I'd be very careful about substituting beef stock or broth instead of chicken. Beef broth is generally more assertively flavored, and usually carries a bit more salt as a counter-balance to that, so changing that flavoring might do a lot more than just alter the flavors slightly.
To illustrate my point, America's Test Kitchen/Cook's Illustrated, in their "best beef stew" recipe wound up using chicken instead of beef broth, because the beef broth was a bit too much. And that was for a beef stew (the recipe is fantastic. They were looking for more rich flavor than just using water, but using beef stock/broth wound up being too much).
EDIT/Addendum - What I was originally going for and lost track of is this - If you have a dish that has a lot of other seasonings or flavors that define the dish, you will probably have better success with a substitution. If you have a dish where the other ingredients compliment the pork or the pork flavor is the key to the dish, you probably won't be as happy.
Depends by recipe.
If you have a named recipe, for example, if you want to make
pasta all'amatriciana you must use pork guanciale.
If you use another meat, you don't make
pasta all'amatriciana but a different recipe.
Generally, if you want to make another recipe (not named) you can change but the flavour can be more different, so it's a great challenge, expecially, you have a restaurant.