What does a novice system administrator need?

Question

IT education

Good day.
There is a desire to go to courses of the system administrator. I just don't know what area to be successful in. If you google "Courses of the system administrator Tyumen", then a lot of links are issued where they teach in different ways. SQL, CISCO, Installing and training Windows Server, FreeBSD, DOS, etc., configuring 1C-Bitrix, training in SCADA systems, TCP / IP, DNS and much more.
What is the best place to start, or what set of "bases" is needed for a novice system administrator (Enikeyschik), which will be really useful for many companies that need a system administrator, and not for a few.
Many thanks for the answers.
UPD:
I'm sorry, I forgot to mention. My knowledge is now minimal, and in different branches. I can install Windows Server and set it up for web (Apache + PHP + MySQL). Similar with Ubuntu Server, Debian. Not much, but I can in html and php. I know how to work with networks in xDSL, FTTx technologies. I can set up network equipment (Wi-Fi routers, modems). I can set up an MFP, IP-telephony. I can crimp the patch cord to 4 pins. That's all I remember so far.

Answer 1

You first need to know: networks (protocols, OSI model, etc.), Linux Centos/Debian, LAMP, Bash scripting, PHP basic.

Answer 2

It is impossible to answer this question without knowing your baseline.
Oracle or Cisco aces are in the price, but are you ready to reach this level after the courses?
What do you know/can do now?

Answer 3

So you already have a beginner base.
Unless you teach Active Directory a little, try it, and set up a proxy for squid.
The rest will come by itself in the process of work.