how to add pagination to child post - php

Question

I created custom post type and child post , i want to add pagination to child post , I've had a basic attempt at this using $paged = (get_query_var('page')) ? get_query_var('page') : 1; and the paged argument in the WP_Query, but my next_posts_link doesn't work.
my code to show child post
<?php
$args = array(
'post_type' => 'programs',
'posts_per_page' => 60,
'post_parent' => $post->ID,
'order' => 'ASC',
);
$parent = new WP_Query( $args );
if ( $parent->have_posts() ) : ?>
<div class="penci-border-arrow penci-homepage-title penci-magazine-title style-5 pcalign-right pciconp-right pcicon-right" style="border-color: #3E68B0">
<h3 class="inner-arrow" style="background:#3E68B0;border-color: #3E68B0">
الحلقات </h3>
</div>
<ul class="penci-wrapper-data penci-grid">
<?php while ( $parent->have_posts() ) : $parent->the_post();
$featured_img_url = get_the_post_thumbnail_url(get_the_ID());
$episode_number = get_field('episode_number', get_the_ID());
?>
<li class="list-post pclist-layout">
<article id="post-<?php the_ID(); ?>" class="item hentry">
<div class="thumbnail child-thumbnail">
<a class="penci-image-holder penci-lazy" href="<?php the_permalink(); ?>" title="<?php the_title(); ?>" style="background-image: url(<?php echo $featured_img_url?>);">
</a>
</div>
<div class="content-list-right content-list-center child-content">
<div class="header-list-style">
<div class="episode-details">
<span class=""> <a class="url fn n" href="<?php the_permalink(); ?>"><?php echo $episode_number ?></a></span>
<span style="margin:0 20px"><a>|</a></span>
<span class="featc-date"><time class="entry-date published" datetime="2021-10-31T13:26:29+00:00">2021-10-31</time>
</span>
<span class='program-viewcn'><?php pvc_stats_update( get_the_ID(), 1 ); ?></span>
</div>
<h2 class="grid-title entry-title">
<?php the_title(); ?>
</h2>
</div>
<div class="item-content entry-content">
<p>
<?php the_excerpt();?>
</p>
</div>
</div>
</article>
</li>
<?php endwhile; ?>
</ul>
<?php endif; ?>