What items are good to buy at Cotsco? I need to fill my refrigerator =)?

iM GOING to Cotsco for the first time Any recommendation in food? My friend invite me to buy my groceries at Cotsco she has membership. What items Cotsco carry at a great price? any recommendation ? I usually buy items like hotdogs, nuggets, chicken breast,ground beef, juice box etc If you shop here can you tell me what items you consider have great discount THANKS!!!!!!!