Unlike traditional laptops, Chromebooks are optimized to help you work in the Cloud. And the Cloud generally never runs out of space.
But every now and then, you may still have a desire to check how much local storage is available. And for those times, Chromebook does have a hidden menu in the files apps.
First open the “Files App” using the launcher and look for the 3 dots on the top right corner. Clicking on that will tell you your available storage status.
If you want more information, click on that item to open another window which looks like the one below. Here you can give a more detailed distribution of how you are using your available Chromebook storage.
This particular screenshot above is from my Chromebook with 128GB internal storage which should be plenty for most of my folks. You can find similar or better device options using the Chrome Device list.