Use Linux on Chrome OS with crouton
Navigate to crouton project page https://github.com/dnschneid/crouton

Run crouton and it will install automatically.
The command below:
-e means enable encryption
-t means the extensions to be installed
-r the Linux distribution going to install (xenial by default)
-n the name you give the installed Linux
sudo sh ~/Downloads/crouton -e -t keyboard,touch -r bionic -n LINUX
To update (e.g. install extra extensions), add -u
sudo sh ~/Downloads/crouton -u -t xiwi -n LINUX
Run desktop if xenial with unity is installed
sudo startunity
To start command line only
sudo startcli
To switch between Linux desktop and Chrome OS
CTRL + SHIFT + ALT + Backward
To exit the desktop environment, logout.
If the color becomes strange, press until normal
CTRL + SHIFT + Reload
To run a specific path or executable without starting the whole desktop
sudo enter-chroot xiwi /path/to/executable
To run it in a Chrome browser tab
sudo enter-chroot xiwi -t /path/to/executable