This plugin adds the "Sign-in with Google / Facebook / Github / Linkedin / Windows Live" buttons on the login page. The first time the user login with a social account, a new Moodle account is created.
- add the plugin into /auth/googleoauth2/
- in the Moodle administration, enable the plugin (Admin block > Plugins > Authentication)
- in the plugin settings, follow the displayed instructions.
More information on the official web site.