There's a distinct difference between screenplay Action and Screenplay Description. Both live in the "Action Description" block under the Scene Heading.
The key is to realize that they are two different important components which go together to introduce and set your scene before any dialogue begins.
The video below explains these distinctions and helps you grasp the discipline with a great visual example of how you can use a real location to prompt your descriptive screenwriting.
The video explains how you can use an environment to inform your scene and pick out only what is necessary according to the genre and story-point. This is presented as the "description" element of screenwriting, which is different from the "action" element. Once you have this concept clear in your mind, you can be clear and efficient about how you lay down your scenes.