If you are a windows administrator, I would not neglect studying windows :-).
"Linux" is unix for the pc with GNU operating system and a linux kernel. Many things are configured from files in /etc.
Distributions 'make life easier' by adding configuration tools, which have the effect of hiding what is actually going on. You need to know sendmail.conf, apache.conf, and how to get by with a 'kill -hup' signal when your urge is to kill the process totally. If you have 1000 users on a web service and apache dies, that's bad news!
Do a LFS http://www.linuxfromscratch.org
. That makes you learn the basics. Red Hat use Selinux, and you might need to learn their tools (selinux and systemd) to survive. Then try doing stuff. Set up a vm with a web service and a email service with spam control and suffer like we all did. you'll learn loads.