Watch each command run in a real-looking terminal, see what every part of it means, then try it yourself with practice tasks. From ls to kubectl.
The first three commands on any server: where am I, what's here, and how full is the disk.
See what's running, find what's eating CPU, send signals, and keep jobs alive after logout.
psSnapshot the running processesBeginnertopWatch CPU, memory and processes liveBeginnerhtopInteractive process viewer with bars and a treeBeginnerkillSend a signal to a processBeginnerkillallSignal every process with a given nameBeginnerpkillFind or signal processes by pattern (pgrep / pkill)BeginnerjobsList the shell's background and stopped jobsBeginnerbgResume a stopped job in the backgroundBeginnerfgBring a job back to the foregroundBeginnerniceStart a command with a lower (or higher) CPU priorityIntermediatereniceChange the priority of a running processIntermediatenohupKeep a command running after you log outBeginner