HELP! Struggling With a Multi Level Category Archive

Hello everyone :)

I'm currently building a site for a local beauty salon and I have come across an issue that I just cannot seem to put my finger on and I have been stuck on this for weeks, where I'm stuck is with the treatments page.

The project requires that I have a treatments page that lists all available treatment categories (massage, waxing, nails, etc). When a user clicks on the treatment category they're after they are then taken to another page that lists all the treatments within that category i.e., Waxing -> Full Leg Wax.

I did a Google search to try and find a good example of what I'm after and I came up with this example and it is exactly what I'm after.

Hierarchy

• List of Treatment Categories (Waxing, Nails, Massage, etc)
  • Individual Treatments (Back Massage, Leg Wax, Eyebrow Tint, etc)
    • Individual Treatment Details (Price, Duration, Description)

I have used a custom post type for the individual treatments, named 'treatments', and then I created a taxonomy called ‘treatment-categories’ (I’ve used the slug names of each). I have used my archive.php template and obviously I have named this archive-treatments.php (code below). I will look at altering the layout of the template once I have this figured out.

<?php get_header(); ?>

<section class="hero hero-sml hero-default no-marg-bottom">
   <div class="container clearfix">
      <h1>
         <?php
            the_archive_title( '<h1>', '</h1>' );
         ?>
      </h1>
   </div><!-- .container -->
</section><!-- .hero -->

<div class="muted-bg">
   <section class="margin-top container clearfix">
      <div class="row">

         <?php if( have_posts() ) : while( have_posts() ) : the_post(); ?>

            <div class="col-4 post-excerpt">
               <article>

                  <a href="<?php the_permalink(); ?>">
                     <?php
                        // Display the featured image
                        if( the_post_thumbnail() ) :
                           the_post_thumbnail( 'small' );
                        endif;
                     ?>
                  </a>

                  <time class="post-date">
                     <?php the_date(); ?>
                  </time>

                  <h3>
                     <a href="<?php the_permalink(); ?>">
                        <?php the_title(); ?>
                     </a>
                  </h3>

                  <p>
                     <?php the_excerpt(); ?>
                  </p>

               </article>
            </div><!-- .post-excerpt -->

         <?php endwhile; endif; ?>


      </div><!-- .row -->
   </section><!-- .container -->
</div><!-- .muted-bg -->

<?php get_footer(); ?>

I have done the same for the treatment-categories taxonomy (archive-treatment-categories), is this the correct way of doing this? Is WordPress even capable of doing something like this? Also just to clarify in case this maybe an issue, I have a blog that utilises categories, tags, etc and a WooCommerce store if that helps.

I really appreciate any help with this, and I'm sure it's one of those solutions where I'll be saying "really, is that all I had to do?". I have been trying this for way too long and it doesn't make any sense anymore to me, I just need another opinion on how to do this.

Thanking you all in advance

Stu :)