How to add a Windows 10 app shortcut to your desktop
First, pin the app to the taskbar. You can do this by right-clicking on the app in the Start menu. Once the app in pinned to the taskbar, right-click on the app in the taskbar while holding down the shift key. Select "Create Shortcut." A window will pop-up asking if you want to add it to the desktop, click yes, and there it is, a shortcut to your favorite Windows 10 app!
Since the whole goal of the Windows 10 app is to have them blend in with traditional Windows programs, this way you can group them all on the desktop, or in a folder of your choice.