You shouldn’t reference the path because the source property is cross-platform and since every platform has a different folder for assets like images, you only need to specify the filename and extension. The Image class knows where to look to find the file.
Image files can be added to each application project and referenced from Xamarin.Forms shared code. To use a single image across all apps, the same filename must be used on every platform, and it should be a valid Android resource name (which means no spaces and special characters). Place images in the Resources/drawable directory with Build Action: AndroidResource . High- and low-DPI versions of an image can also be supplied (in appropriately named Resources subdirectories such as drawable-ldpi , drawable-hdpi , and drawable-xhdpi ).
var beachImage = new Image { Aspect = Aspect.AspectFit };
beachImage.Source = ImageSource.FromFile("waterfront.jpg");
Source: https://learn.microsoft.com/en-us/xamarin/xamarin-forms/user-interface/images?tabs=windows#local-images