After seeing the video how-to setup your kubernetes cluster with Rasberry Pi’s, I started to build my own mainly to learn kubernetes. It helped a lot to get started. I have made also made lot progress with it (cert-manager, nginx-ingress etc…). Last weekend I have migrated the container engine from docker to containerd. Maybe this procedure might interest you. You can find it here
https://www.debontonline.com/2020/12/kubernetes-part-13-replacing-dockershim.html
Thank you, I’ll have a look at that as soon as I can.