Flutter auth

I need someone to help me develop a user authentication system for my app using Flutter. The authentication process should include both email/password and Google sign in. In addition, I will need a registration form that allows certain user roles to be assigned. It should also provide a secure sign-in experience. The developer should also be able to provide advice on strategies to ensure the user data remains secure and protected.

i need this type authentication and google ads customer id or manager account data.
First check this app authentication i need this :- https://play.google.com/store/apps/details?id=com.cleverppc.cleverads&hl=en&gl=US

it;s so urgent work so don't west Time.