As promised in a previous announcement by Google, a pre-release of Steam for select Chromebooks has been released for ‘people to try.’
The release is compatible with a select group of higher-end Chromebooks that meet the requirements which include an Intel Iris Xe Graphics, 11th Gen Core i5 or Core i7 processors, and at least 8GB of RAM.
To date, Google has verified a select array of games are in fact compatible with Chromebooks including Civilization V, Portal 2, and the Elder Scrolls; with some of the games requiring the higher-end part of the requirements to work.
You can visit here for instructions on how to install Steam on your Chromebook.