Here are some common kubectl commands that I find myself using.
get namespaces
kubectl get ns
get deployments
kubectl -n NAMESPACE get pods
get pods
kubectl -n NAMESPACE get pods
logs
The below command will returns logs for multiple container with the label
kubectl -n NAMESPACE logs -c CONTAINER_NAME -l app=LABEL_VALUE -f
describe pod
kubectl -n NAMESPACE describe pod POD_NAME
ssh to pod
kubectl -n NAMESPACE exec -it POD_NAME bash