WP posts with multiple categories

Hello guys, when I’m searching the categories in the menu. I choose one link and it gives me everything that there is but how can I find posts that are having both categories at the same time? I’m looking for all posts that are having both of them, so is there a way to filter them like that?

There is no way to show post from 2 categories one a single menu automatically.
Yes, You have to create a custom page temple and write some custom code to show posts from 2 categories. You will have dive in WordPress code to do that.