If you have products from multiple brands, you can configure them in this section. Brands can be identified using Attributes, Collections, or Product Vendor (Shopify Default). For Example, there are multiple brand products whose data is stored in Attributes. Add the following values as mentioned below.
Do you sell products of multiple brands: Yes
Identified Using: Attributes
Select Attributes: Here you can select all those Attributes which store Brand information.
Refer to the following image for a better understanding.