https://docs.magento.com/m2/ce/user_guide/catalog.html

CATALOG

In this section of the guide, you’ll learn how to create categories and products, upload images, establish pricing, and set up your inventory.

Products

Learn how to create products from simple to complex with multiple options, swatches, customizable bundles. Create downloadable products, and virtual products for services and other non-tangible items.

Categories

Learn how to organize your catalog into categories that are reflected in your store’s navigation.

Product Attributes

Learn how to create attributes with input controls for product options, and to provide additional information on product pages.