How to delete large files for Steam and other apps
The Steam system for games makes it easy to purchase and download games onto a variety of devices you own across multiple computer platforms. Steam acts as a combination of platform, offering some gaming features available to all the apps it supports, and a purchase and copy-protection system. The key part, though, is that when you download a Steam game, the program code is wrapped up and loaded in a way that Steam can use.
However, to macOS, each game can still seem sort of like a standalone app. That becomes important only when you’re trying to clean out storage on your Mac to free up space.
One of the easiest ways to find items that you no longer need is to select > About This Mac, click the Storage tab, and then click Manage. A window appears that calculates storage consumed across several categories, and lets you select items to delete directly.