Hello Gurpreet0101Singh-9444,
Please note that if you are using Workforce tenant, then currently the feature to configure Custom OIDC Identity Provider is not supported.
But if you are using External tenant, then the option to configure Custom OIDC Identity Provider is currently supported.
I have reproduced this scenario in my test tenant and I am attaching you the Screenshots below taken from both Workforce tenant and External tenant.
Workforce tenant:
External tenant:
Note:
Please note that the above two Screenshots were taken without configuring any additional settings in both the tenants.
If you are using External tenant, then you can add OpenID Connect as an external identity provider by following the steps as mentioned in the below document.
Add OIDC for customer sign-in - Microsoft Entra External ID
Please note that below are the supported built-in and custom identity providers which can be configured and used in Workforce tenants.
1.Microsoft Entra accounts
2.Microsoft accounts
3.Email one-time passcode
4.Google
5.Facebook
6.SAML/WS-Fed identity provider federation
Please refer to the below document for your reference.
Identity providers for workforce tenants - Microsoft Entra External ID
Please refer to the below Screenshot which shows the tabular column comparison of supported Identity providers in both Workforce tenant and External tenant.
Reference document which will be helpful:
External Tenant Features - Microsoft Entra External ID
I hope the above provided information is helpful. Please reach out to me if you have any further clarification or queries.