You can start with minikube, it’s a one node environment you can run in a vm. Another fairly straightforward kubernetes distribution is k3s, you can set it up on a bunch of nodes running common linux distributions via ansible for example.

I learned how to kubernetes from open online sources and just trying really hard to set up certain apps. Some have kubernetes tutorials or deployment manifests included.

You can also start with helm, which is like a package manager for kubernetes. It can ease you into configuration required for each application.

As for docker, kubernetes uses containers, but those are bundled into pods. It’s not a particularly difficult leap I think. However I recommend trying using podman for a bit first. It’s fairly compatible with dockerfiles and commands, but also allows you to setup and export pods you can then directly use in kubernetes.