The CTA means the ‘call to action’ - it’s the action that you’d like your customers to take when they see a personalized message on your website. When creating a message you have two options in terms of what you’d like your CTA to be:
Close message adds a button to the message that lets your customer dismiss it quickly and easily so they can continue looking at your website.
Redirect visitor to a page adds a customizable button that allows you to guide your customer to a different page, e.g. your booking engine.