Hi @Matab ,
Currently we only support SCIM for gallery applications and for non-OIDC custom/non-gallery apps. I believe that also means "only for SAML non-gallery apps" but I'm not positive if there may be a third+ option there. You should be able to work around this by creating two non-gallery apps, one for OIDC SSO and one for SCIM provisioning.
To create a gallery application, you need to be a software vendor that has a SaaS application that is a multi-tenant/multi-customer app. This document describes how to go about getting your application added to our gallery: https://learn.microsoft.com/en-us/azure/active-directory/develop/v2-howto-app-gallery-listing
To the best of my knowledge we don't have any license requirements around creating a gallery or non-gallery app or using provisioning. There are some extra features such as assigning groups to applications that require AAD Premium licensing, but that is not core functionality.