Which NCL ship will you be sailing upon?
Briefly, all NCL ships will have two FREE main restaurants, a FREE buffet, and several FREE specialty restaurants, usually the Italian restaurant and several fast food court grills.
What you pay a surcharge for are:
(1) Le Bistro - serving French cusine.
(2) Cagney's Steakhouse (or East Meets West) - serving larger steaks.
(3) Asian Restaurant ( names vary by ship) - serving Asian cusine usually including a Sushi Bar and Teppanyaki tables.
(4) On two NCL ships, the Norwegian Sun and Pride of Aloha, the Italian restaurant has a surcharge but on the rest of NCL's fleet the Italian restaurant is FREE. Those with a surcharge serve more upscale Italian menus than your basic pasta dishes and are worth the extra fee.
Not every ship, as you can see above, have all the restaurant choices. Older-smaller ships have less choices.