Calling specific page with wp query

by

You need to add a meta query, which will specifically select those posts that have both the meta key you want, and the desired value. 

$args = array(
    'post_type' => 'pages',
    'order' => 'ASC',
    'meta_query' => array(
     array(
        'key'     => 'use-this-page-as-a-section', // or whatever the key is
        'value'   => 'yes'
     )
 );