This theme has 8 other widget areas, but this particular page doesn’t display them.
You can navigate to other pages on your site while using the Customizer to view and edit the widgets displayed on those pages.
From here you can add widgets to the following section –
To add a widget click any of the sections and then click on the Add Widget button.
The widget list will show up. From the search bar, you can search for any available widget. Just click on the widgets you want to add and they will be added to the section.
Your selected widget is added to the section. Now you can add a title and set some options to the widget. Click on the Done button to save the changes.
When all the customization is done click on the Publish button to save your theme.