Html or Php assistance

I have a plugin that feeds in a long set of web addresses into one list. I want to display these links as simple “register” where the user can click the register text and follow the link. I have used href to do this and it works. The problem is some of the entries do not have links (you cant register yet) but the text “register” will appear no matter what. I was hoping to find a way where when there it no link to follow that the text would be automatically hidden. The plugin still uses the its own value, so it is not just blank.

Register

The %event_custom_field{Registration}% sometimes is a link and sometimes is not.

This is the page I am trying to do this on… https://www.scnca.net/event-list/

Really hoping there is a way to do this!

I appreciate any kind of help on this!

Thanks