Hello!
Actually the page you've screenshoted presents links to different demonstration pages. Each of these demonstration page are of special type "project" (in WP you've, of course, posts and pages but you have other types too like projects and testimonials). The first page (which contains mac screens as links) is just a special page generated by my theme to presents all the "projects" of the site. It's not from my plugin, it's done by the theme (Divi, actually) is use.
Don't hesitate to tell me if it's unclear, my English is a bit... poor!
Pierre