Only one row of my posts displaying in the front page

Here is my site:
https://photoselfiea.com/

Thanks for your reply, Pratik.

I’ve followed your instruction. The “more post” button is working and by clicking, it changes to a new page showing all of my blog posts. But the front page still only displays one row of my posts.
Is there another option I need to change from the theme customizer?

I have copied verity-pro/template-parts/recent-posts/front-recent-posts.php and pasted at verity-pro-
child/template-parts/recent-posts/front-recent-posts.php and changed the ‘posts_per_page’ to 12 (like below) but nothing has changed after I’d uploaded & installed the verity-pro-child.zip which includes style.css for the child theme. Am I missing anything here?

Below codes shows only part of the whole codes in the file.

<div id=”infinite-post-wrap” class=”archive-post-wrap”>
<?php

/**
* Show eight latest posts excluding first one
*/
$recent_posts = new WP_Query( array(
‘posts_per_page’ => 12,
‘post__not_in’ => array( $first_post_id ),
‘ignore_sticky_posts’ => true,
‘paged’ => ”,
) );

/* Start the Loop */
while ( $recent_posts->have_posts() ) :
$recent_posts->the_post();

get_template_part( ‘template-parts/content/content’, ‘archive’ );

endwhile;

wp_reset_postdata();
?>
<div class=”posts-navigation”>
<div class=”nav-links”>
“>

Finally, it’s working. There are so much to learn. Thank you so much for your support. Pratik.