get child taxonomy wordpress (ok)

https://developer.wordpress.org/reference/functions/get_term_children/

C:\xampp\htdocs\wordpress\wp-content\themes\twentytwentyone\header.php

<?php
				$term_id = 33;
				$taxonomy_name = 'genre';
				$termchildren = get_term_children( $term_id, $taxonomy_name );
				echo '<ul>';
				foreach ( $termchildren as $child ) {
			    $term = get_term_by( 'id', $child, $taxonomy_name );
			    echo '<li><a href="' . get_term_link( $child, $taxonomy_name ) . '">' . $term->name . '</a></li>';
				}
				echo '</ul>';
				?>