Changes

Keep the Create new Firebase Project option selected and enter Firebase Notification Demo into text the field. Select your country from the drop-down menu, click on the Connect to Firebase button and wait for notification from Android Studio that the connection has completed successfully.

As part of the process of connecting the app to the Firebase project, a file named google-services.json will have been added to the Android Studio project. To locate this file, switch the Project tool window from Android to Project mode using the drop-down menu: