[keycloak-user] How can I use Keycloak to support my architecture?

Hi, I need some help in securing my applications with keycloak: I have couple of grails applications (App1 and App2) using spring security. However, currently I am using keycloak REST API to authenticate users by passing username and password and receive token without registering these applications as clients in the keycloak. But this approach seems to be inefficient when we want to support SSO, kerberos and other lot of powerful features that Keycloak offers. So I came up with the below approach to support SSO/kerberos but wanted to know if Keycloak can solve our problem. "Create a new spring boot master application (App3) and register with Keycloak and redirect the login page to Keycloak. Once login is successful, use the token that keycloak provides and pass it on to App1 and App2 and tweak my existing code flow to handle this. Can this be possible because I am not registering/creating any clients for app1 and app2 in keycloak here but only creating for app3 which is the master application and using the access token? Is it mandatory to register/create all clients in Keycloak to support SSO?" Any help would be highly appreciated. Thanks in advance!