I'd start by addressing the end of your error: "Предупреждение
An unexpected error occurred trying to initialize Android Designer.
Please verify the Android SDK path and the Java Development Kit
path on Tools->Options->Xamarin->Android Settings menu.
Please see the logs for more details. 0"
ya'ni Android SDK yo'lini va JDK yo'lini tekshiring (agar kerak
In Visual Studio this is under Tools > Options > Xamarin
> Android Settings. I don't recall having to set any
environment/path variables, I know Android Studio used to need
things in the path but I think Visual Studio/Xamarin didn't ask for
them, or maybe they were already set so it didn't need to ask.