No - although you do need a selling platform of some sort, whether it's online or offline.

For example some members will use platforms like: Gumtree, eBay, Amazon, flea markets, classified ads, local markets, brick and mortar stores, or trade magazines.

For sellers who are new to wholesale, eBay is one of the easiest ways to start a business online, but make sure you take a look around at the other options as well.