learning_bee15 on "How do I only show excerpt not the full post on homepage?"

Hello All,
First let me clear I am very novice with PHP and I am trying to edit Twenty Fifteen theme . On home page it shows the full content of the blog post. I want to show only the excerpt.
What can I do?

This is my index.php.

<?php
/** * The main template file * * This is the most generic template file in a WordPress theme * and one of the two required files for a theme (the other being style.css). * It is used to display a page when nothing more specific matches a query. * e.g., it puts together the home page when no home.php file exists. * * Lea more: {@link https://codex.wordpress.org/Template_Hierarchy} * * @package WordPress * @subpackage Twenty_Fifteen * @since Twenty Fifteen 1.0 */
get_header(); ?> <div id="primary" class="content-area"> <main id="main" class="site-main" role="main"> <?php if ( have_posts() ) : ?> <?php if ( is_home() && ! is_front_page() ) : ?> <header> <h1 class="page-title screen-reader-text"><?php single_post_title(); ?></h1> </header> <?php endif; ?> <?php // Start the loop. while ( have_posts() ) : the_post(); /* * Include the Post-Format-specific template for the content. * If you want to override this in a child theme, then include a file * called content-___.php (where ___ is the Post Format name) and that will be used instead. */ get_template_part( 'content', get_post_format() ); // End the loop. endwhile; // Previous/next page navigation. the_posts_pagination( array( 'prev_text' => __( 'Previous page', 'twentyfifteen' ), 'next_text' => __( 'Next page', 'twentyfifteen' ), 'before_page_number' => '<span class="meta-nav screen-reader-text">' . __( 'Page', 'twentyfifteen' ) . ' </span>', ) ); // If no content, include the "No posts found" template. else : get_template_part( 'content', 'none' ); endif; ?> </main><!-- .site-main --> </div><!-- .content-area -->
<?php get_footer(); ?>

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