Display hero button if meta key is not empty

functions.php

<?php
/**
 * Plugin Name: Listify - Custom Single Listing Hero Button
 */
function custom_listify_single_job_listing_actions_after() {
    global $post;
    
    $url = get_post_meta( $post->ID, 'your_custom_meta_key', true );
    
    if ($url != "") {
      echo '<a href="' . esc_url( $url ) . '" class="button">My Button</a>';
    }
}
add_filter( 'listify_single_job_listing_actions_after', 'custom_listify_single_job_listing_actions_after' );