The most easy way I know of is this.
You can run a few linux choices in a browser online.
If you want you could set it up offline.
Microsoft offers a Services for Unix package that allows quite a few posix commands. Not really good for learning.
There used to be a company that wrote dos based unix commands to learn linux with also. I forget that company name. They offered it with a book for free.
Slackware still offers a very old Zipslack for easy testing but you would have to run it in a vm as XP won't allow umsdos anymore I think.
Any of the ideas above should work.
Also you have ways to run a usb flash drive or a cd or even a floppy that has linux.
You can even boot off the internet to a linux OS run in memory at www.netboot.me
Someone still offers a mirror to boot.kernel.org for the old fedora net boot.
There may still be some other ways to try.