Identity Cloud supports three types of authentication for the signup and login flows:
Different authentication methods can be configured for each authentication type under the Signup/Login > Authentication section of the Management console. See details for each under the respective chapter in this section.
The authentication settings applied under Signup/Login (referred to as default settings going forward) apply globally to all users, unless you override them with organization specific settings.
To manage the registered authentication methods of users go to the Authentication methods tab of the users' details.