Render a Post or Page using the correct file

Assuming you have the post id’s already I would use them in the page delimiters. For this you’d need to create one main div per post and use the post id as a css class or id. Within that post you’d have to adapt the loop to load only the content of that id.

like this:

Say the id of the post is 100. you could call the main div for that post:

<div id="post-100" class=""></div>

within this div you’d have to adapt the loop to load only the content of that post. You can do this like this:

$queryArgs = array( 'p' => '100' );
$newQuery = new WP_query($queryArgs);   

Then you’d have to change the loop to this:

<?php if($newQuery -> have_posts()):?>                        
    <?php while($newQuery -> have_posts()) : $newQuery -> the_post();?>      
        <?php the_title(); ?>
        <?php the_content(); ?>
        // or whatever code you want to place here
    <?php endwhile; ?>
    <?php wp_reset_postdata(); ?>
<?php endif; ?>  

if you repeat these steps for every post id you’ll be able to do exactly what you want to acheave.

Let me know if you need any more help or have any questions.