Hi Christian,
To clarify, do you mean you want to display the category on the top of a post?
If so, you can do this using Header Elements found in WP Admin > Appearance > Elements.
I believe Coach theme already has a Posts Title Header element by default. This controls the display you see on single posts’ page hero header.
When you edit it, this is the default you’ll see.
<h1>
{{post_title}}
</h1>
<p class="post-tags">
{{post_date}} | {{post_author}}
</p>
You can add {{post_terms.category}}
if you want its category to display.
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