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When I learned this stuff I started with The Debian Administrator's Handbook (https://debian-handbook.info) and an O'Reilly book called Unix Power Tools. Since then I've read handbooks for whatever servers/frameworks/apps I needed to use. There was never one single source. I've also spent lots of time googling error messages and reading Stack Overflow/Server Fault and other sites.

This is a good start: https://www.ansiblefordevops.com/

I usually provide this as an intro:

http://www.linuxcommand.org/tlcl.php/

From there picking up configuration management should be pretty straightforward.