Then you clearly do not understand credit cards!
With a credit card, you buy something this month, say July 5th, you will get an invoice by mid August and it needs to be paid in full at the end of August. If you do that, then you pay NO interest at all, you pay the amount you have purchased for and that's it.
It's when you DO NOT pay the full monthly amount that you start to pay interest on the sum you "borrow" by not paying it off in full. As long as you pay in full, each month, there are no extra fees or interest rates to pay.