category excerpts and pagination

Hi

How can I manage the pagination for the category, i.e. show 10 excerpts per page?
Right now it’s showing 3 on page 1, and 4 for page 2 and 3, and 0 on page 4.

Also did I do it correctly, or is there a better way to show only excerpts of the posts in the category page?
By searching, I found this
https://www.dailyblogtips.com/how-to-make-category-pages-display-post-excerpts/
so I changed the category.php like this:

<?php while ( have_posts() ) : the_post(); ?>
<?php // following is the original quark code showing full article
// get_template_part( 'content', get_post_format() ); ?>
<?php // this is to show only excerpts
the_excerpt() ?>
<?php endwhile; ?>

Thank you

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