Setting up a dual-boot with Linux and ChromeOS on a managed PC

Hi, I wanted to know how to set up a dual-boot system or run Linux from an external drive on an ARM-based PC (model CM1406CM4A). I’m aware that this PC lacks a standard BIOS meaning it uses a different bootloader and requires an ARM-specific distribution. Also, the PC is managed by a company or institution, so many features (like developer settings) are locked down. Basically, I want to know how to boot Linux from an external drive and use the PC within that Linux environment, without leaving traces of my activity on the main OS when I unplug the drive (I have a technical background in IT).

simple: you cannot