Step 1: Prepare the USB Installer
On a working computer, open Google Chrome browser.Install the Chromebook Recovery Utility extension from the Chrome Web Store: Or click the link below and Install.
https://chrome.google.com/webstore/detail/chromebook-recovery-utility
Open the extension and click “Get Started”.
Click “Select a model from a list”
Manufacturer: Google Chrome OS Flex
Product: Chrome OS Flex
Insert your USB drive and follow the instructions to create the bootable drive.
Step 2: Boot Your Laptop from USB
Insert the USB into the laptop where you want to install Chrome OS.
Reboot the laptop and press the boot menu key (usually F12, F9, Esc, or Del depending on your laptop brand).
Select the USB drive to boot.
Step 3: Try or Install Chrome OS Flex
Chrome OS Flex will load. You’ll see an option to either try it or install it.
For More Info Watch The Below Video Tutorial