Everyone has a Wi-Fi network at home and everyone is happy to let guests use the Wi-Fi if they wish. This is not without its problems, as the passwords are fairly easy to read on all devices.
So briefly entering the guest's Wi-Fi password on their smartphone without them seeing it is ultimately pretty pointless. Even sharing via QR codes or direct sharing, as is possible between iPhones, does not prevent the guest from never seeing the password.
If you don't already know it, a quick web search will quickly show you how to make these saved passwords visible. Depending on the device, you may need an additional app or it can be done quite simply without any tools in the existing settings.
FS-TIP: If possible, always set up a separate guest WLAN that provides pure Internet access and cannot reach any other resources in the network.
