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.
terraform, ansible and puppet: plan, apply and converge infrastructure from code.
terraform initPrepare a Terraform working directoryBeginnerterraform planPreview what Terraform will changeIntermediateterraform applyCreate, change or destroy real infrastructureIntermediateterraform stateInspect and repair Terraform's stateAdvancedansibleRun one task across many servers (ad-hoc)Beginneransible-playbookRun Ansible playbooks to configure serversIntermediatepuppetEnforce server configuration with PuppetIntermediate