There are two parts to this article:
You can use metadata to organize your products into collections for your stores. When you are creating a product, upload a photo and save your changes. After that, you can add values or attributes to that product in the Metadata section. Here's what you will see:
When you apply a word to the field under Value, that product will be associated with a tag that you can add to a collection. For example: if you upload a photo of a shirt, the value you assign could be Clothing.
Any products that contain the value tag Clothing will be grouped into one collection. When you assign those products to a collection (you do this by navigating Products > Collections), you can add that value, Clothing, here.
When you are creating a product, the section just below Metadata is SEO. You have the ability to edit the Title and Description for this specific product.
Customizing your Title and Description will help customers who are searching for your product to better understand what they can find before clicking your link. The more accurate your copy is, the higher probability customers will search & discover your product.