How to see the functions of a button in wordpress?

How to see the functions of a button in wordpress?
Hello everyone, I currently have a theme installed called SSAGENCY (it is a theme for casting, models, actors and actresses), this theme has a button that is used for my clients to apply to the castings that I as an administrator have created. I would like to know how I can know how that button works (how I can see its code) and thus be able to copy what it does so that another button that I create in elementor does this task.

What happens is that when I graphically change that publication, everything is visible (the text, the images, etc.) except the button to apply to that casting, so what I want to do is insert a new button with that function.

The button that works and comes by default with the template is only visible with the SSAGENCY theme, but when I change the graphic appearance by creating a post content in elementor the button disappears.

I appreciate everyone’s collaboration, if you require more detailed information I can gladly provide it.