To show subpages you can use page-list plugin.
Or you can add this code to functions.php:
<?php function wp_list_subpages(){ global $post; $children = wp_list_pages('title_li=&child_of='.$post->ID.'&echo=0'); if($children) return "<ul>".$subpages."</ul>"; } add_shortcode('subpages', 'wp_list_subpages'); ?>
And then you can use this shortcode [subpages] inside of your page content to show list of subpages.