I think you are referring to the panel shown in the screenshots above like this.
Firstly I have Playing Tracks showing in the right sidebar panel which you can select from the Arrange Panels icon or the View menu.
The [DJ] next to the Tracks header shows that AutoDj has been activated by pressing the Shuffle button on the main player and click until the headphone symbol is displayed. You can also activate AutoDj directly from the Controls menu.
You need to have a couple of parameters set for AutoDj and you can do this by right-clicking on the Tracks[DJ] header which will bring up a menu from which you can select Auto-DJ Settings which will in turn open a new tab for the settings screen as below:
On this Screen you can set various parameters for AutoDj.
The example below shows that I want 15 tracks selected when I turn it on and that I want a minimum of 5 tracks to always be available in the Tracks Playing list. You can also select how 'random' should be treated and various other options. If you click the preview button it will show a list of what's going to be played in the lower part of the panel.
Hope this answers your question and is of help to you.