This article explains how to share Wi-Fi network passwords using Wi-Fi Sense in Windows 10. Wi-Fi Sense does not exist in Windows 10 v1803 and later, so if your computer is fully upgraded, you will not be able to use it.
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Wi-Fi Sense lets you quietly share Wi-Fi passwords with your friends. Previously a Windows Phone-only feature, Wi-Fi Sense uploads your passwords to a Microsoft server and then distributes them to your friends. The next time they're in range of that network, their devices will automatically connect.
Wi-Fi Sense should be enabled by default on your Windows 10 PC, but check to make sure it's active.
Select the Start button, then select Settings.