​First you list the products that you want to sell on Amazon.in marketplace. Customer sees your product and makes a purchase. You will receive a notification to ship the product. You deliver the product to the customer and confirm shipment or let Amazon fulfill the order for you through FBA or Easy ship.
Amazon Sellers, Sell On Amazon, Selling On Amazon                 

Amazon will charge whichever of these two is higher for each item: a. Referral Fee as a percentage of sale price. It ranges from 6% to 20% (45% for Amazon devices), but it's usually 15%.
Amazon Sellers, Sell On Amazon, Selling On Amazon

​SELLING ON AMAZON WITHOUT EAN / UPC CODE. Unlike eBay or other online marketplaces, where each seller has its own listings. While listing a new item on Amazon, it should be matched to an existing listing in the Amazon catalog. In order to perform such a matching, Amazon requires UPC/EAN/ISBN codes
Amazon Sellers, Sell On Amazon, Selling On Amazon                 

​It is only paid after you have successfully sold an item. When you ask yourself, should I sell on eBay or Amazon, whether you have an eBay store is key. If you don't have an eBay store, you pay a 10% fixed fee. ... Now, to work out the answer to question of should I sell on eBay or Amazon, you need to Amazon's seller fees.
Amazon Sellers, Sell On Amazon, Selling On Amazon                 

​Doing their research by ordering as secret shoppers, they discovered that over 70% – that's OVER SEVENTY PERCENT – of their product sold on Amazon by third-party sellers was counterfeit. Only when they filed a lawsuit did Amazon BEGIN to cooperate with them. BUYER BEWARE.
Amazon Sellers, Sell On Amazon, Selling On Amazon