How to hide the catalog categories from the block?

If you need to hide all catalog categories at once, go to the Block Settings → "Filters & Store Categories" and select the "Hide the list of catalog sections" checkbox. Then save the changes and re-publish the page.

If you want to hide one specific category only, go to the catalog management panel → Product Categories.

Then click on the pencil icon near the category you need and select the “Hide the list of catalog sections” option.