
The Sales and Service areas do not show up for me on the Stie Map even though I have system administrator access. I think the site map was probably customized.
I need the Case and Order entities to be accessible, how can I add them there?
Actually I don't have access to a Dynamics 9.0 on premise environment but you should be able to do that under Settings -> Customizations -> Customize the system then under Components choose client extensions (on the left side) and open the Site Map on the right panel.
Consider that what you see in sitemap browsing Dynamics could be filtered using "permission" but it should not be your case because you are a system administrator.