@Zoey Cotton: Did you check in the Theme Instruction at http://catchthemes.com/theme-instructions/catch-everest/
I am not so clear about your questions.
The Mount Everest Image and the text with it is the Slider. You can change that by assigning Post ID in Featured Post Slider. For that
1. First create the Post and don’t forget to add in the Featured Image in the post as this image is used in the slider. To add featured image see this http://en.support.wordpress.com/featured-images/#setting-a-featured-image
2. Then get the ID of the post. When you edit your post or write a post, you will see the id in your browser address bar. You will also be able to find the post ID when viewing your all posts. But if you cannot find it then you can use this plugin to view it http://wordpress.org/extend/plugins/catch-ids/
3. Then go to “Appearance => Theme Options => Featured Post Slider”. Add in the post id.
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