Close your apps
You can close your apps two ways:
Click the X:
Simply click on the X button on the very top right corner of the window you are viewing to close that window or exit that app.
Exiting full screen displays:
If you cannot see an X button, you can exit the app by pressing the Esc key on your keyboard, which is usually on the left-hand corner of your keyboard. The window should close completely or become smaller so that you can see the top bar of the window and the Endless task bar at the bottom. If the window becomes smaller, you can then click the X to quit.