Do Keycloak Clients have a Client Secret?

Client need to have the access-type set to confidential and you can see the client Secret in credentials tab

Your client need to have the access-type set to confidential , then you will have a new tab credentials where you will see the client secret.
https://wjw465150.gitbooks.io/keycloak-documentation/content/server_admin/topics/clients/oidc/confidential.html