Enable Single App Mode in Apple Configurator 2
Single App Mode forces the selected app to open on the supervised device and prevents the use of other apps. When this payload is active, the app reopens immediately after the device is restarted.
In Apple Configurator 2
on your Mac, select a device or Blueprint on which you want to enable Single App Mode.Choose Actions > Advanced > Start Single App Mode.
Select which app will be the only app available for use. Click Options to view the features available in Single App Mode.
Choose any options, click Apply, then click Select App.
For information about the options available, see Single App Mode features.