It is just a linux distro. Not a handsome one either. "Every" IT person needs to learn how to use Windows Server first before jumping onto these things because 90%+ companies are using Windows Server.
No it’s a BSD.
I usually say to layman that they are different forks of unix from many years ago.
OpenBSD and Linux have a lot of the same tools to be sure but they are different enough that you have to learn them both if you are administering them.
You are also exposing your own severe ignorance.
And you are exactly the sort of person who needs to read the article.