Hello @siva pokuri ,
Thanks for the ask and also for using the Microsoft Q&A forum.
Unfortunately, it is not possible to change the authentication to Azure AD B2C.
Reason: Databricks is able to auth using the AAD tenant which is linked to the workspace. Azure Active Directory B2C users are not typically in the tenant so that are not able to log in to the Databricks workspace. They would need to be a guest at minimum.
Hope this helps. Do let us know if you any further queries.