Hi there!
If I understood correctly, what you’re after is selecting posts for a certain category, right?
To do that, just add this parameter in the shortcode:
taxonomy=”category=4″
and replacing ‘4’ with whatever your category ID is in your system.
Cheers!
Oh, #Inmilla, if your portfolio entries are pages and not posts, you can attach categories to those too, ie by using the https://www.ads-software.com/plugins/post-tags-and-categories-for-pages/ plugin.