It is strongly recommended that you take the "Linux Essentials" course on Linux if your Linux skills are not quite at this level.
"Distribution," on the other hand, refers to the pairing of the kernel with a user-land built to some specification.
Ubuntu, for instance, varies quite a bit from Cent OS 6. Unlike operating systems, which are built in a monolithic fashion (where the user-land and kernel are tightly-coupled, such as Free BSD, VMS, Windows, etc.), Linux allows for variations on theme which number into the thousands.
Any virtualization environment will do, provided you have access to the console, as it may be necessary at various points.
Actual hardware is also acceptable, if those resources are readily available to you.
All files fall into two of the four categories, without exception.