Post hyperlink to external URL

I am using the Coral wordpress theme and it has a featured section on the front page where it displays an image and text as four slides. You can see it here – dev.360yardware.com. Each slide is a post with the title, content and featured image used by the slide. When a user clicks on a slide it takes them to the post. Now what the client would like is when they click on a slide instead of taking them to the post it takes them to an external URL. Is it possible to change the hyperlink on a post to point to an external url without affecting the content of the post which the theme needs to display?
thank you