Ok first, Right click anywhere on the screen. And select new, then shortcut. Here it will ask you to navigate and select the app for which you want to create a shortcut for Just paste this text in the box. You copy it from the description below. Now click on next. Here it will ask you to rename the shortcut button and rename it as per your need. Finally click on finish.
There you have it your shortcut button to easily shutdown your computer just double click twice on this shortcut and your system will be shutdown.