Display static pages instead of category, in code

It seems like you are trying to change a theme to your own needs?
Since you do not need the categories. etc. You could just drop that whole piece of code starting at

   $featured_categories = array(8,9,10);



Next put in your own html code. With links to your pages. Probably 3 times this.

<div class="featured-category-footer">
    <a href="https://wordpress.stackexchange.com/questions/61973/link to page">link</a>

If you want these pages to come from your wordpress.
Look into wp_list_pages and change it to your needs.