Displaying Related posts | WordPress.org

Hello, I have been trying to display the related posts on my single.php but I cannot figure out why it’s not working properly. This is the code I am using. I am also using bootstrap with this code all the related posts are getting lined under each-other instead of being next to each other.

I will appreciate it if you could help me to replace it with a better code.

<?php get_header(); ?>

<?php foreach( $related_posts as $related_post ) : ?>
    <h3><a href="<?php echo get_permalink( $related_post->ID ); ?>"><?php echo get_the_title( $related_post->ID ); ?></a></h3>
    <?php echo get_the_post_thumbnail( $related_post->ID, 'thumbnail' ); ?>
<?php endforeach; ?><?php
// Get the tags for the current post
$tags = wp_get_post_tags( get_the_ID() );

// Get an array of tag IDs
$tag_ids = array();
foreach ( $tags as $tag ) {
    $tag_ids[] = $tag->term_id;
}

// Query for related posts based on the tags
$related_posts = get_posts( array(
    'tag__in' => $tag_ids,
    'post__not_in' => array( get_the_ID() ),
    'posts_per_page' => 
) );

// Loop through the related posts and display the titles and thumbnails
foreach ( $related_posts as $post ) {
    setup_postdata( $post );
    ?>
    <div class="container"> <!-- container start -->
      <div class="row overflow-hidden"> <!-- row start -->
	   <div class="col-xs-6 col-sm-6 col-md-6 col-lg-4 col-xl-3">
		   <div class="title-box mx-auto mb-0">
        <a href="<?php the_permalink(); ?>">
			    <h1 class="title-color">
			<?php the_title(); ?></h1>
         <?php
                        if( has_post_thumbnail() ):
                            the_post_thumbnail('full', [ 'title' => 'Feature image', 'class' => 'img-fluid']);
                        else:
                    ?>        
                        <img class="img-fluid" src="<?php echo get_template_directory_uri() . "/images/bg.jpg"; ?>">
                    <?php endif; ?>     </a>
            </div>
		     </div> 
		      </div> 
		       </div> 
    <?php }wp_reset_postdata();?>

<?php get_footer(); ?>

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