category Posts to Excerpts

Hi, I am using Aldehyde Theme and have searched and searched and am still confused as to how to change the category from showing full posts to excerpts.

Do I change this in Archives.php?

<?php /* Start the Loop */ ?>
<?php while ( have_posts() ) : the_post(); ?>

<?php
/* 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() );
?>

Is this what I should be looking at?

thank you ??