... and if you want instead to buy
a virtual-machine host (e.g. VMWare), so that you are not distracted by setting up VirtualBox, you can do that also.
You definitely need to get your hands dirty with the tools, in a hands-on situation where Linux itself is "a means to an end" ... a means of getting to
the true system-of-interest which is the embedded system. VMs are a very good way to set up arbitrary environments without disturbing the host system. You're probably going to find many different Linux distros in use, but once you get a few of them under your belt (by using them as a means to an end), the pragmatic differences between them start to fade until "you can pretty much get into any
car, and drive."
(As my parents said when I was learning to drive, "well, your first car probably shouldn't be a Porsche ("damn!" )
but mostly what you need is a really big, empty parking-lot to drive around in.")