With Drive File Stream, you stream your Drive files directly from the cloud to your Mac or PC, freeing up disk space and network bandwidth. Because Drive files are stored in the cloud, any changes you or your collaborators make are automatically updated everywhere.
To open a file, click the File Stream icon in the system tray
then click the folder to open the Drive Folder
You can also make Drive files available for offline access. These cached files sync back to the cloud when you're online, so the latest version is available on all your devices.