Advertisers need a Bing Merchant Center store to do Bing Shopping Campaigns. Bing Shopping Campaigns allow advertisers to use Product Ads. The Product Ads are then created from the content of the Merchant Center catalogs, including custom images, promotional text, price, and other details.
The Bing Merchant Center is created in Bing Ads. On Bing Ads, click on Tools and then select Bing Merchant Center. Click after in Create store.
Retail advertisers need to fill the store info, including the Store description and the Checkout page that needs to be secure (https). Retailers can also block aggregators here. Advertisers need also to verify the domain via Bing Webmaster Tools or via Universal Event Tracking (UET) tag, this last one, allows advertisers to track conversions (like purchases or leads) or target audiences using remarketing lists.
Advertisers can create multiple stores but are not allowed to sell the same products through multiple stores.
If the store is created now you can advance with the feed creation:
Advertisers can view here the feed rules for Bing Merchant Center.
The last step is create a shopping campaign. From the Campaign page, click Create Campaign, then click Shopping campaign. You will be prompted to add your product extensions and campaign targeting parameters.