The Management UI allows configuring (nearly) everything that can be configured on your idaas.nl tenant.
The management UI uses the exact same APIs as you would use from your organization's applications or you use from PostMan.
The sidebar is the main navigation pane. It provides you with access to everything you will need to configure your tenant.
Many settings can be found using the search bar. Start typing and several setting pages will show.
While making changes to your tenant using the Management Panel, open your browser its developer tools (with F12) and go to the Network-tab. It will show you all API calls you can re-use in your scripts or use in Postman.