This is a paid asset, but now you can download Google Login Addons for FREE, Please keep in mind this package is provided only for learning purposes or to be able to test before buying the product, NOT FOR COMMERCIAL PURPOSES.
Detail this asset from Unity Store: Original Link
[MFPS] Google Login Addons v1.0.2
“If possible, please buy the package to support the developer”
Google Login Allows users to sign in/sign up in ULogin Pro with Google Accounts using the Web OAuth 2.0 API,
adding an extra way to users to create accounts in your game quick and painless process.
■ Sign In and Sign up.
■ Work on all platforms.
■ No third-party plugins required.
■ Build-in tutorial to set up the Google API Credentials.
■ Custom redirect page.
■ 1-Click Integration.
This addon requires ULogin Pro and a SSL certificate for your domain.