Enable Google Sign-In in the Firebase console:
Read moreHow do I add firebase authentication to my flutter app?
Implementing Firebase Authentication in a Flutter app
Read moreHow do you use phone authentication on flutter?
Enable Phone Authentication in Firebase All you have to do is click enabled. Then download the google-services. json file again, and add it the project under android/app . Note: If you want to authenticate using email/password then check this tutorial: Using Firebase Auth In Flutter.
Read moreHow do I integrate with Google sign in?
Integrating Google Sign-In into your web app
Read moreHow do I integrate Google login in flutter?
Flutter – Google Sign in UI and Authentication
Read moreHow do I sign into Google account on Android?
Integrating Google Sign-In into Your Android App
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