You can just link to the RSS feed. It will then be possible to click the link and directly open the podcast in any proper podcast app, not just AntennaPod (unfortunately, users seem to migrate to closed platforms recently - those usually don’t support proper standards). If your RSS url does not end with
xml, it might happen that some systems don’t recognize it as a podcast feed. In that case, you can be more explicit and use
itpc:// instead of
http:// in front of the url (itpc stands for iTunes podcast but the protocol is still supported by most “real” podcast apps). Do you know the podlove subscribe button (https://subscribe-button.podlove.org/)? It displays a list of podcast apps when clicking, based on the device that you are using.
If you explicitly only want to link to AntennaPod, you can also use
antennapod-subscribe:// instead of