How to enable Sidebar filters?

First, you need to add attributes. You can add attributes to products under Edit product > Miscellaneous > Attributes.
Once the attributes are created, follow the steps:

1. Go to Design theme > Design section.

2. Click on More variables > Miscellaneous.

3. Click on Sidebar sections. Add a key value pair “filters:Apply Filters” separated by a comma from other key value pairs.

4. Save all changes.

It will be available for any theme or for any store now.