Custom authentication module


We have a requirement to have custom authentication module in keycloak such that along with userid / password two other authentication methods should be shown. These two autentication methods should show form on keycloak login page and when user enters auth credentials these modules will make external web services call to authenticate through external web service and then create keycloak session. Please provide suitable suggestion to achieve this, I have looked into examples authentication provider secret / question however I am not able to get some hints through it. My main question -
1> How to show the three tabs (1 for each authentication types in keycloak). ?
2> First authentication type is default one available in keycloak (user id password form).
3> Other two authentication accepts certain parameter like phone no and makes (present on user record in keycloak) and makes web service call and then authenticates user.

Any hints will be appreciated.

Thanks in advance,