On Android 7.0 and higher, once you have enabled the Developer Options in system settings, you can find the Demo mode option. And below it, you can find the Enable Demo mode and Show Demo mode options. So what’s the difference between them?

Enable Demo mode
Enable Demo Mode allows you to change the appearance of the status bar using adb demo mode commands. This doesn’t hide any thing from your status bar until you use adb demo mode commands to do so.

Show Demo mode
It will hide notifications and display a preset status bar. This resets the status bar to temporarily remove notifications, set a time and hide the current time, sets the signal and battery levels, etc.
Show Demo mode makes it easier to take clean screenshots by displaying a generic, hide any notifications, your current time, carrier name, or low battery warnings.