A template for displaying Advanced Custom Fields flexible content rows programatically without having to list each row individually.

content-flexible.php

<?php
/**
 * Partial template for ACF flexible content
 *
 * @package Understrap
 */

// Exit if accessed directly.
defined( 'ABSPATH' ) || exit;

the_title( '<h1 class="entry-title d-none">', '</h1>' );

// check for ACF flexible content data
if ( have_rows( 'modules' ) ) {

	// loop through the select ACF flexible content layouts
	while( have_rows( 'modules' ) ) {
		the_row();

		// dispaly the matching flexible content partial
		get_template_part( 'modules/' . get_row_layout() );
    
    // Just add your row templates into a directory named `modules` in the root of your theme
    // Each row template shoud have a filename matching the ACF slug
    // (ex: three-columns.php for a field with slug `three-columns`)
	}
}

template-flexible-content.php

<?php
/**
 * Template Name: Flexible Content
 *
 * Template for displaying ACF Flexible Content Modules
 *
 * @package Understrap
 */

// Exit if accessed directly.
defined( 'ABSPATH' ) || exit;

get_header();

?>

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

	<div class="container-fluid" id="content" tabindex="-1">

		<div class="row">

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

				<?php
				while ( have_posts() ) {
					the_post();
          // Get the template part for looping through our flexible content fields
					get_template_part( 'loop-templates/content', 'flexible' );

					// If comments are open or we have at least one comment, load up the comment template.
					if ( comments_open() || get_comments_number() ) {
						comments_template();
					}
				}
				?>

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

		</div><!-- .row -->

	</div><!-- #content -->

</div><!-- #page-wrapper -->

<?php
get_footer();