Community administrator can setup the Google based authentication for the login and signup of the members to their community. This makes the signup and login process easier. You would need to generate the 'Client ID'using the Google account, to setup the google based authentication on the community. If the Google Client ID is not generated and saved in the Social Login under Settings, then the user will not be able to sign up or login using his/her Google account.
After login you will be able to configure the project for your community. Click Configure a Project button as in the image below and give a name to your project.
After creating project, click on Next.
The generated client ID need to be added and saved in the Keyfield highlighted in the image below. The path for this is Community >> Set Up >> Social Login >> Google as below :
This feature is available with the following license :