How to make the Filterable Attributes In Layered Navigation

To set up layered navigation with the attributes filterable, you can follow 3 steps: 

• Step 1: Set up the attribute properties
• Step 2: Make the category an anchor
• Step 3: Test the results

The details for each steps, please refer in here: 

https://docs.magento.com/user-guide/catalog/navigation-layered-filterable-attributes.html