You can add sections to a list or modify the existing sections.  You will need to create at least one section before you can add library items to the list.

To add a section, click the New Section button and give your section a title.

To edit an existing section, or one without a title, right click on the three dots and choose Edit Section.  You can also add a description and control the visibility of the section by adding in dates.  Be sure to press Save.

To move a section, click on the bullet list to collapse the section view..

Hover over a section to highlight it and then drag the little blue bar to move the sections up and down.

Once you have created a section, you are ready to start adding items.