Yeah, we'd need a lot more information before we could begin to help you in a more meaningful way.
I don't say this to be cruel, but you seem to have little to no idea about what you are doing. You say you opened this location in April? But you also opened it 2 years ago? Is it seasonal? Or do you have multiple locations?
Everything everyone else said is 100% right of course. You seem to be confusing some terms as well. Food cost is how much money you spend on food. You should not have to estimate this number...you (I assume) have invoices and receipts from all your purchases for food, so all you have to do is add them up to get the amount of money you spend on food.
The food cost percent is how much of a percentage you spent on food as it relates to your gross income. The lower you can get this number, obviously, the more money you have to spend elsewhere and/or profit.
There are a few ways to go about this. If indeed it is true that you have hardly no waste and sell everything you make before it goes bad, then I would look at a couple factors first.
The first thing I would do is make sure your prices are where they should be. If you don't charge enough for your food, you won't make money. In fact, I've seen places that actually end up loosing money on some items by the time labor and other things are factored in. You need to know how much money it costs you to put a portion of food on a plate and make sure you are making money at the price you are selling it at.
Do you use a lot of pre-made, frozen, convenience food that you either deep fry or reheat? Things that you "just add water" to and pull out of the freezer? These things, while convenient, are (at least as a general rule) more expensive than the house-made alternative. If you, for example, use pre made frozen chicken fingers instead of cutting and breading your own chicken, you are almost assuredly paying more. Same thing goes for soups, sauces, onion rings, hush puppies, etc.
Are your employees stealing from you? Hey, I'll let you in on a secret. If you run a restaurant/kitchen, your employees WILL steal from you. I would say that 100% of restaurants in the country have some form of "theft." Theft can be things like making themselves lunch, sending a friend an order of "free" fries, drinking soda. It can, of course, be more damaging and obvious things like walking home with a steak wrapped in clingfilm in their pocket, or taking money from the till, or alcohol, or office supplies, toilet paper....the list goes on.
I'm not suggesting that everyone in every restaurant is a thief...though that also might depend on your tolerance level and what you consider theft. Is the waitress drinking a Coke really a THIEF? It depends on your definition and what you allow....if you allow employees to have a cup of coffee or two in the morning, or to make themselves chicken sandwiches for lunch, that is OK and totally up to you. You just have to know and account for it.
I don't know if Sam's Club is cheaper than a vendor....I would think that Sam's Club would still be more expensive than ordering things from a vendor, but I haven't done a lot of shopping at Sam's Club so I don't know. Just make sure that you are looking at more than one vendor so you can bargain shop and get the best prices.
Did you know you can sometimes negotiate with vendors? A lot of chef's don't do it, but you can sometimes talk them down...especially on meat and fish prices. Never hurts to ask for a deal. Say..."hey listen, I'm thinking of putting tilapia on my menu, but your price is a little higher than I would like. I'm going to be buying a lot of tilapia in the next 6 months, is $8 a pound really the best you can do?"
You might also try a book search on amazon for basic restaurant food cost and controlling costs in restaurants. There are many out there....