List-item.php Add function

How to add:

<?php esc_html_e( join(", ", $cc) ) ?>

Custom fields

on title:

My code:

<span title="<?php esc_attr_e( get_the_title() ) ?>" class="advert-link"><?php get_post_meta( get_the_ID(), "my_custom_checkbox", true); ?> - <?php the_title() ?></span>

But dont work.
https://wordpress.org/plugins/wpadverts/