You can send people a link to the subdomain that you signed up for when you created your Airtime Pro account. In the case of Sourcefabric, for example, we'd link people to https://sourcefabric.airtime.pro.
You can also click the Radio Page tab in the navigation bar on the left side of the Airtime Pro interface, and it will take you to the page you should send listeners to. You can copy that URL to share with your listeners.
Select Settings > Streams > Output Streams > Stream URL to find your direct listening link, which will be required if you are submitting your radio station to any online radio directories such as TuneIn, etc.