If you intend to insert a button with a custom link within the header image of a particular post / page, with Attesa PRO you can do it.
NB: to do this, the featured image must be set to “Big Featured image in the header”.
Edit or create a new post or page, go in the “Attesa Extra Theme Options” box, select the “Post Settings or Page Settings” and you’ll find an option called “Use custom button in the header“.
Check this option to insert the button text, button link and choose to how to open the link (same or new window).
The result will be as in the screenshot below, obviously the colors and the font will be those set on your website.