IdP initiated sso login from Okta using keyclock as broker that redirects to my portal with auth code

I have identity provider as Okta. I am using Keycloak as Identity broker between IdP and to my portal.
I am trying to achieve this-> from Okta app, user will do IdP initiated sso and Idp send saml response to keyclock, Keycloak need to redirect to my portal with the authorization code.

Is this possible to achieve?
I have done sp initated flow to get authcode to my portal. That is working.( I created saml identity provider, OIDC client in keycloak and created an app in Okta)

What are the extra steps to do, to achieve IdP initiated sso from Okta that will redirect to my portal with authcode.