ok..
With Windows, only Microsoft offer versions, yes?
With Linux, because it's open-source, you have lots of companies and individuals offering different "versions".
These "versions" are known as distributions or distros for short.
I suggest you spend a few days with Google doing some research, so that you understand what you're getting yourself into

There is so much choice and it will confuse you to begin with.
Not only are there hundreds of different distributions, all with a particular aim, there are also different desktop environments (DE's).
Oh then there's the release cycles, Windows releases a new version every few years, in Linux they come a lot quicker, usually every few months. So you could choose a distro to use now, install it and find that the one you've chosen has been superseded a few days later - it will still work just fine but you won't have the latest unless you upgrade. Which is why it's important to do your research.