Previously I wrote about Windows Update behavior in Windows Server 2016.
So at this point there is no way to change Windows Update behavior from GUI in Windows Server 2016 and the default value is "Download Updates only".
To change this:
1. Open Command Prompt.
2. Type sconfig
3. Select 5, to configure Windows Update
4. Select on of three options - Manual (which never checks for updates), DownloadOnly (which is default and only downloads updates), Automatic (which downloads and installs updates automatically)