How to Turn Off Automatic Updates in Windows 10
Microsoft has made it very difficult for the average user to disable Windows updates like you could in Windows 7. The option to turn off Windows updates in Windows 10 has been removed from the control panel completely.
Disable the Windows update service in Windows 10 following these steps below. Note this will disable the service responsible for checking, downloading and installing updates for Windows and other programs including Windows Defender. It is recommended to perform Windows updates for security updates and Windows Defender (if you use this built in antivirus program) manually at least once a month.:
Step 1: Click on START menu and type Services in Start menu or taskbar search box and then press Enter key.
Step 2: In the right column scroll down to Windows Update and double click on it.
Step 3: The box below appears, change the Startup type to Disabled. Click Apply button and then reboot your computer.
Other things you can do to prevent Windows 10 from doing automatic updates, see this page.