In computing, a virtual desktop is a term used with respect to user interfaces, usually within the WIMP paradigm, to describe ways in which the virtual space of a computer's desktop environment is expanded beyond the physical limits of the screen's display area through the use of software. Wikipedia 
Google is adding virtual desktops to Chrome OS, the first parts of which became available in the Chrome OS Version 76 stable channel.
Chrome Unboxed describes how the features of virtual desktops work. page
The Chrome OS virtual desktop capability appears to be patterned from Mac OS' capability. I don't use Mac OS much so never really use virtual desktops in it. page
Windows 10 also has virtual desktops, which I don't use too much. IMHO the important keyboard sequence is Ctrl+Windows key+left arrow / right arrow to toggle between desktops. page