external hdd boot up

I have an older computer that I can't afford to replace.
I have come up with an idea that I want to know if it will work.
I have a company computer that gets replaced every couple of years or so. It came with a docking station that is not being used.
I am wondering if I can load up an external hdd with an os and all my stuff. When wanting to use my home computer I could boot up using the external hdd with the laptop in the docking station with my 22in monitor, printer etc hooked up.
That way my home stuff stays separate from my work stuff.
Thanks

 

Does the bios of the laptop recognize a USB external device as bootable?