understrap/page-templates/vertical-one-page.php

<?php
/**
 * Template Name: Vertical One Page
 *
 * Template for displaying a page without sidebar even if a sidebar widget is published
 *
 * @package understrap
 */

 get_header();
?>

<?php
/*
 * Exclude the posts page from being shown in this layout.
 * Order pages by their order number.
 */
 $exclude = get_option( 'page_for_posts' );
 $args    = array(
  'post_type'    => 'page',
  'post__not_in' => array( $exclude ),
  'orderby'      => 'menu_order',
  'order'        => 'ASC'
 );

 $qry = new WP_Query( $args );
?>

<div class="wrapper" id="full-width-page-wrapper">

  <div class="container" id="content">

    <div class="col-md-12 content-area" id="primary">

      <main class="site-main" id="main" role="main">

        <?php if ( have_posts() ): while ( $qry->have_posts() ): $qry->the_post() ?>
          <div class="page">
            <?php get_template_part( 'loop-templates/content', 'verticalpage' ); ?>
          </div>

          <?php wp_reset_postdata(); //reset custom query?>
        <?php endwhile; endif; ?>

      </main><!-- #main -->

    </div><!-- #primary -->

  </div><!-- Container end -->

</div><!-- Wrapper end -->

<?php get_footer(); ?>