To get rid of the Get Office notifications you would need to remove the Get Office app from your Windows 10 PC. Here is how:
1. Got to Start then Settings to open the Settings Window.
2. In the Settings, click on System tile.
3. Under System choose the Apps & features from the left side.
4. On th right scroll down the list of installed apps to select Get Office app from the list.
5. Click on the Uninstall button to remove this app from your system.
Once the Get Office app has been removed, you will no longer see Microsoft Office advertisement notifications on your Windows 10 system.