If your computer does support 64-bit, here is the correct process. Google does provide a raw ISO for direct flashing. Instead, you use the Chromebook Recovery Utility (a Chrome extension) to create bootable USB media.
Before Google acquired Neverware, (the precursor to Chrome OS Flex) offered a 32-bit version for legacy devices. That version is now end-of-life and receives no security updates. Using it online is dangerous, and Google has removed all official download links.
These distributions run well on the same hardware you wanted to use for Chrome OS Flex. They also offer traditional ISO downloads that you can burn to a USB with tools like or BalenaEtcher .
Searching for a can be a confusing experience because official support for 32-bit architecture has effectively ended. Google designed ChromeOS Flex specifically for x86-64-bit Intel or AMD processors. The Reality of ChromeOS Flex 32-bit
Have a 32-bit machine you successfully revived with Linux? Let us know in the comments below. If you found this post helpful, share it with someone still hunting for that fake ISO.
Here is the breakdown of why this is the case, the risks of trying to force it, and the best alternatives for your older hardware.