/cgl/ - Cosplay & EGL

Question. I'm new to doing Artist Alley. I did my first one at NYCC recently which went better than I expected.
So recently I was asked if I'd like to apply for a table at a convention in New Jersey. Only problem it, it says under their rules and regulations for exhibitors that I need a NJ Sellers Permit. Specifically:

>"Exhibitors are responsible for collection and payment of New Jersey State
taxes and must obtain any required Sellers Permit"

Now I didn't need one for NYCC but this convention is saying I do. Thing is, I'm from New York. So what exactly kind of sellers permit do I need to sell at this convention and where would I apply for one?