Add some additional information about viewing Group level Packages

doc/user/packages/package_registry/index.md

@@ -21,6 +21,12 @@ You can view packages for your project or group.
 
 You can search, sort, and filter packages on this page.
 
+When you view packages in a group:
+
+- All projects published to the group and its projects are displayed.
+- Only the projects you can access are displayed.
+- If a project is private, or you are not a member of the project, it is not displayed.
+
 For information on how to create and upload a package, view the GitLab documentation for your package type.
 
 ## Use GitLab CI/CD to build packages