Hi there,
It is best to set up your PC online with a Microsft account so it would be easier for you to access the laptop in case you forget your password. Once your updates have been downloaded, it is not necessary to have an internet connection. But if you want the best out of windows 10, then it is good to have an internet connection.
To disable Windows 10 Automatic Updates:
-Go to Control Panel - Administrative Tools - Services.
-Scroll down to Windows Update in the resulting list.
-Double click the Windows Update Entry.
-In the resulting dialog, if the service is started, click 'Stop'
-Set Startup Type to Disabled.
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