You need to get the sales tax exempt certificate/ID number from your state dept of revenue. This allows you to collect sales tax and get the tax exemption when appropriate. A Federal ID has nothing to do with a sales tax ID.
As said earlier, you should pay sales tax on stuff consumed in your business but not stuff for resale. So, disposable utensils, straws, soda, take-out containers, condiments, napkins etc are tax exempt. Disposable food pans you use for large take-out or catering orders are also exempt, where as those you use in your own steam tables are not. You need to supply the store with a copy of your sales tax certificate each year.