I want to have the same behavior of 'https://support.zendesk.com/hc/en-us/categories/360001735874'
where if I select an element of 'Browse common questions' (I think they are labels of the articles) the related sections are shown below.
How could I do to have the same operation as the page shown?

Hey Gustavo,
We actually use custom code in our Guide theme to accomplish this. While I'm not able to assist with any Guide customization on my end, we do have some great resources available that I would recommend you look at.
Customizing your Help Center theme (Guide Professional and Enterprise)
Help Center CSS Cookbook
Help Center Templates Introduction
Help Center Javascript Cookbook
Tips for using HTML to customize your Help Center
Zendesk Partner Directory
Zendesk Themes Directory
I'll leave this post open in case other users can jump in and offer up some additional advice.
Cheers!