In this section, you can add all the facets that will be displayed either on the Top or Left side of the Search Results Page and change their setting as well. In the first row when you click on Add New, 3 columns are to be filled for each Facet you want to add which are as follows.
Field: Choose the filter you want to add on the Search Results Page
Label: Have a custom name for the field you have chosen.
Position: You can either choose Left or Top, depending on your requirement
If you have added multiple filters and want them to be collapsible, i.e. the customer can close and open the filters on the Search Results Page. And you can choose the default behavior of the same.