The Listing Config section allows you to configure the columns that are displayed for each of the Workflows you have created.
In the (below) example, you can see the different columns that have been configured to be shown in the datable for the Workflow - Quality Control Check.
These are made up of default fields and (optional) available fields.
Please note that just because you have configured the fields to be shown in the datatable it doesn't mean you have to use them.
It simply means that you have the option to include them, and that they will be selectable from the dropdown.
To set up your workflow datatable please follow this guide