This is true marketplace where sellers can list items at fixed prices and even open their own "shop".
Essentially, how it works is for seller to list items, add photos and descriptions and choose price. When deal has been made, the buyer makes payment via one of 2 payment options (With crypto or from wallet deposit), and product will send automatically after payment is complete.
While it may be free to list an item (depending on how many items you list in month), the seller pays fee when item is sold. In addition, the seller usually pays fees associated with payment method your buyer uses. There are other services that you can choose to pay for.
When transaction is complete, the buyer and seller give each other feedback about sales process and/or goods sold. Kingdom has many rules to protect buyers and sellers, so before you start, know the rules first.