Open the Windows Store, search for “Windows Defender Application Guard Companion” and install it. Press the Windows button and search for the newly installed App. Right click the symbol and pin it to the taskbar. When you click the symbol, a Microsoft Edge Application Guard window will open. This is not what “Windows Defender Application Guard Companion” was developed to be used for, but it works. If you know a a more simple way to start WDAG please let me know.