This is exactly what I did. Download a bunch of iso images and use a USB thumb drive or burn them to disc.
If using thumb drives, make sure you delete all hidden files when burning a different Distro to it so it's clean.
I would suggest going to https://distrowatch.com/ to read about the types of OS on offer.
Think of it as,
Linux is a car,
Distros (Distributions) are the manufacturer (Toyota, Ford, Kia, Audi) and
the DE (Desktop Environment) is the model line (Prius, F150, Sorento, A6).
You need to choose a Distro and a DE.
Distros to check out, Mint, Ubuntu, Kubuntu, Pop!_OS, Fedora, OpenSUSE. This will give you a variety to test a "live disc", no need to install right now.
DE's to test, KDE, Gnome, Mate, Unity, Cinnamon.
Most Distros are completely re-installed 2x a year with April and September being the release months.
You can find LTS (Long Term Support) versions of many Distros. These are installed once and updated regularly for 3-5 years.
And lastly there are Rolling Distros that are installed and updated in perpetuity.
I personally settled on Kubuntu LTS. It's a KDE (Plasma desktop). It's very easy to customize when you get a little experience, but not necessary to customize at all. I've been using this for over 12+ years.
Play around with some Distros, take some notes on what you like. You can dual install with Windows if you want/need to.
And remember, Live discs (USB) are just a testing ground, changing settings will not save if you test the same Distro again.
Always choose the "Try" or "Live" option in the boot menu and it won't mess up your computer.
And backup your current data before doing any of this. Better safe than sorry.
Kpop is cool and all but not a great way to see the differences in people. Kpop idols are routinely made to look like other popular idols to appeal to a larger fan base. This happens in other cultures as well, US actresses for example!
I would suggest you stick with Dramas to get a better mix of people. And mix it up by country. Add some Thai, Japanese and Chinese dramas to your watch list. At some point you will see the vast differences in just one nation, China is quite diverse in looks, Thailand as well. And it can't hurt to experience music and dramas from other parts of Asia like Vietnam, Malaysia, Singapore, etc.
And don't just limit yourself to Asia, really look at humanity. You would be surprised how often you can see the similarities between cultures. American Eskimos having Chinese traits. And I don't mean eyes, facial architecture varies worldwide.
In America people think anyone Hispanic/Latin is Mexican (which is SOOOOO false). But Central and South Americans are just as diverse. The larger the mix of people from a continent you are exposed to, the easier it is to get a sense of where they may be from.
All of humanity migrated from someplace, and we still do today.