Click Select Drive and choose the Chrome USB Drive you have created. Click Flash to begin the process of installing the image and validating the installation. Once Etcher finishes, this will be a bootable USB drive with Chromium OS.
Chrome OS gathers all of its resources from internet throughout use. A minimum of hard drive space will be required, too, negating the need to buy a high-end computer, because it was developed for Net-books. The preferable method to install Chrome OS from a USB drive.
‹ › This means I’ll leave the Chrome OS install on the internal drive and install Linux on a always plugged in USB 3.0 thumb drive. USB 3.0 drives provide fast read/write speeds and a compact one like the SanDisk 128GB Ultra Fit is the one I chose.
unfortunately it isn't possible to change it, this is due to Chrome OS "requiring" a secure boot however it can boot without it. You should be able to change your BIOS to a legacy based boot to which this should then work for you. This will work for a USB drive too but you have to use "chromeos-install...