Hi, I'm assuming that you are currently using a windoz box (Windows PC) ... or at least that's the OS you're most familiar with, suggestions above are all good, especially those recommending installing into VirtualBox before installing directly to your hard drive. VirtualBox is easy to learn and Well Worth the effort. (And it's free).
Debian (stable) or Debian based distro is what I'd recommend off the bat, there are a lot of them out there, just check
Distrowatch.
Of the distros listed at the above link, you'll learn the most going with Debian itself but depending on your hardware it can be a little tricky for a newbie to set up codecs needed to get all hardware running.
You might actually learm more yet trying to pick up Arch or some of the other above mentioned distros but my guess you may end up without any hair before you learn how to do what you want to do using it.
If it were me learning from scratch (all over again) I'd choose
SolydK. I'd suggest checking out their forum.
What the SolydXK forum lacks in quantity (it's a very small but helpful group) it makes up for in quality. It's one of the most "newbie friendly" forums I've ever been to. You'll get answers to questions fairly quickly and anyone there will do whatever it takes to help you get a problem figured out.
I suggest SolydK because the KDE desktop is going to seem more familiar if you are coming from windoz.
I like KDE desktop because it's so customizable later on when you get familiar with it.
The above is just my opinion, there are likely many pros and cons to following this advise but for what it's worth, it's based on many years of distro hopping, trying to escape the MS trap they call windoz.
I'm proud to be completely MS free for the last half a decade ... learning about the Linux kernel and what it can do is an awesome journey, one you will never regret!
Just dig in, do a ton of googling, read, read and read more on the forums of your choice, ask questions, watch videos, do as many tutorials as you can and before you know it you'll know your distro infinitely better than you ever knew windoz. (Can ya tell I'm not much of a windoz fanboy ... lol).
CW