Add functions to page

Hi there

I’ve spent more thant two hours looking for an answer, but i’ve got the impression i am too noob to understand this 🙂

I only want to add the <?php get_page_hierarchy( $posts, $parent ) ?> somewhere, so that every page shows the hierarchy at the top of the page (body). It should be something so simple…

I’ve read about the functions.php, but there are many and i use Headway Themes to customize my Themes by drag&drop, so all the general files always redirect to something with Headway.
I don’t get it… 😛

Thanks for help, kind regards