Display inner pages like posts.[Like how post excerpt works]

By default, the page post type does not show the excerpt box like posts, but you can enable it like this(code goes into your theme’s functions.php file):

add_action('init', 'excerpt_for_pages');
function excerpt_for_pages() {
    add_post_type_support( 'page', 'excerpt' );
}

Then you can see the excerpt field when you edit your page. If not, make sure it is turned on. Click Screen Options in the top right corner and make sure Excerpt is checked.