A useful code snippet to display a post's categories on a single page or within a loop.
<?php $categories = get_the_category($post->ID);
foreach( $categories as $category ) : ?>
<a class="card__category" href="<?php "". print home_url() . "/category/" . $category->slug . "/" ?>"><?= $category->cat_name; ?></a>
<?php endforeach; ?>