Need info about resale certificates,licences, and fees?

Hi i'm interested in selling online and ebay. The company i would be purchasing my goods from says i need a resale license. What exactly is this? Is it the same as a resale certificate? If I buy goods just to resell are there taxes i have to charge. What are the fees of a resale license. Do I have to file my year end taxes any differently? any help would be appreciated