Notifiarr is a client interface for Notifiarr.com, a fancy thing-doer for integration with the various apps, as well as with a Discord server.
Once you've enabled it in your account, launch the app via your dashboard.
If necessary, use FileBrowser to navigate to /config/notifiarr and adjust the config, and then trigger an app restart by either shutting it down (it'll auto-restart), or restarting it from your user dashboard.