Your Facebook Shop or Instagram Shopping accounts are your sales channels. These are where buyers can discover and purchase your products. They are both implemented on a common back-office infrastructure provided by Facebook Business Manager and Commerce Manager. Your commerce settings are configured on a Facebook page, which refers to product listings from your Product Catalog.
Many companies already have a Business Manager account. Please work with your Marketing or Social Media department to gain access to your Business Manager if you have an existing account. You'll then be able to add your Facebook Page or claim your Instagram Account, and configure your Shop back-office using Commerce Manager.