Open the DNS zone which you want to connect with Dynamic URL. Find the A or AAAA record which you would like to be updated dynamically and click on the arrows on the row for this record. Afterwards, you have to Activate the Dynamic URL in the pop-up. Once you do it, you will see example scripts, used for record update. In this setup, you will need the macOS script. Download it.
Dynamic DNS on macOS can be configured using PLIST job with Launchd. To do so, download the macOS script from the Dynamic DNS pop-up. Next, you can move the file to a directory of your choice and load the job in Launchd using the following command in Terminal:
% launchd load /path/to/dynamic-url-macos.plist
Once you are ready, the Dynamic DNS will be succesfully configured.