To re-enable the lock screen in Windows 10, repeat these directions, but choose Disabled at the last step. If you edited the registry to make the change, you can delete the value you added.

Or, use the Ctrl + Alt + Delete keyboard shortcut, then select Lock. Windows 10 includes Dynamic Lock, which automatically locks the screen when your phone is out of range.

Windows 11 shows widgets on the lock screen. If you want you can remove the Lock Screen Widgets in Windows 11 by following this post.