Source: templates/archive-lesson.php

<?php
/**
 * The Template for displaying lesson archives, including the lesson page template.
 * This template also handels the lesson modules taxonomy and the lessons_tag taxonomy.
 *
 * Override this template by copying it to your_theme/sensei/archive-lesson.php
 *
 * @author      Automattic
 * @package     Sensei
 * @category    Templates
 * @version     2.0.0
 */

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

get_sensei_header();

/**
 * Action before lesson archive loop. This action runs within the archive-lesson.php.
 *
 * It will be executed even if there are no posts on the archive page.
 *
 * @hook sensei_archive_before_lesson_loop
 */
do_action( 'sensei_archive_before_lesson_loop' );
?>

	<?php if ( have_posts() ) : ?>

		<?php sensei_load_template( 'loop-lesson.php' ); ?>

	<?php else : ?>

		<p><?php esc_html_e( 'No lessons found that match your selection.', 'sensei-lms' ); ?></p>

	<?php endif; ?>

	<?php

		/**
		 * Action after lesson archive  loop on the archive-lesson.php template file
		 * It will be executed even if there are no posts on the archive page.
		 *
		 * @since 1.9.0
		 *
		 * @hook sensei_archive_after_lesson_loop
		 */
		do_action( 'sensei_archive_after_lesson_loop' );
	?>
<?php get_sensei_footer(); ?>