That will depend on the platform as iOS and Android and UWP use different Maps by default. But as I check the native map views, only iOS MKMapView (https://developer.apple.com/documentation/mapkit/mkmapview) offers a UserLocation property. Android.GoogleMaps.MapView (https://developer.xamarin.com/api/type/Android.GoogleMaps.MapView/ ) does not, so therefore Xamarin.Forms Map ( https://docs.microsoft.com/en-us/dotnet/api/xamarin.forms.maps.map?view=xamarin-forms) does not either. (In general Xamarin.Forms only offers properties that are common to all native APIs).
But why do you want to get it from the map itself? Why not just get it using the User location APIs for which there is a cross platform library you can use: https://docs.microsoft.com/en-us/xamarin/essentials/geolocation?tabs=android
The above library can be used in a Xamarin.Forms project or in a Xamarin native cross-platform project.
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