GitHub apps for Organizations


reading the docs and the different libraries, it’s not very clear to me how I can achieve the following.
For my App, I want a an organization admin to be able to install my app in their organization, but make it impossible to be installed on a single repo or for a user. Authentication should ideally be happening via oAuth.
All the docs seem only to have more generic use cases in mind, or cases, where apps can be installed for repos or single users.

What’s the proper way of doing this?

Open a ticket to the support team