View file wordpress/wp-content/themes/twentytwentyone/template-parts/excerpt/excerpt.php

<?php
/**
 * Show the excerpt.
 *
 * @link https://developer.wordpress.org/themes/basics/template-hierarchy/
 *
 * @package WordPress
 * @subpackage Twenty_Twenty_One
 * @since 1.0.0
 */

the_excerpt();