Actually Wi-Fi designates WLAN, and this cannot be used for navigation.
The car can create a Wifi hotspot, but this is only to connect mobile devices to one mobile connection (e.g. using 4G or 5G).
However the speed is often very low across Europe, there are lot of places where even 4G does not work properly unfortunately.
Otherwise you could connect your mobile phone which is running a navigation, and use the NAC only to display it.