Good evening Roger and welcome to the Events Calendar forum!
Thank you for reaching out to us.
I would love to help you with this topic.
if it is possible to change the appearance of the URL displayed from use of the Pro Additional Fields. I’d like to switch it to a button that says “Buy Tickets” versus just showing the url.
The short answer is absolutely. This can usually be done with a bit of CSS.
To achieve this, you might need to slightly tweak the meta box in the single event view.
The good news is that we have made this easy to do.
You might want to read our Themer’s guide to get a sense of how that works.
From there, you can simply use one of the many simple tutorials out there on how to turn links into buttons.
We even have one: https://theeventscalendar.com/knowledgebase/url-as-word-button/
Let me know if that helps.
Have a great day!
Geoff B.