Authenticating Using kubectl
In vSphere with Tanzu, authentication is performed using vCenter Single Sign-On. You run the command kubectl vsphere login to authenticate a user through vCenter Single Sign-On to Kubernetes clusters.
kubectl vsphere login --server <kubernetes control plane> -u <username> The --insecure-skip-tls-verify flag is required if the certificate presented by the vSphere with Tanzu control plane is not trusted by the client machine. The control plane is signed by the vCenter Server VMware CA by default. You can replace the control plane certificate with a trusted certificate if needed. Alternatively, install the vCenter Server VMware CA root certificate into your client machine to remove the need for the --insecure-skip-tls-verify flag.

For some parts of your application (for example, frontends) you may want to expose a Service onto an external IP address, that's outside of your cluster.
Kubernetes ServiceTypes allow you to specify what kind of Service you want. The default is ClusterIP.

A ReplicaSet declares how the functionality of a pod is made scalable and resilient through redundancy. The ReplicaSet ensures that a specified number of pods is kept running. Example: Deploy a ReplicaSet. * The ReplicaSet name is nginx-replica-demo. * Two replicas are expected to be running. * The ReplicaSet applies to pods with label nginx.
For more information about Kubernetes replica sets, see https://kubernetes.io/docs/concepts/workloads/controllers/replicaset/

A Supervisor Cluster namespace is a combination of resource allocations and permissions set within the Supervisor Cluster. When you create a Supervisor Namespace, you'll assign who has access to use it, and how many of the ESXi cluster's resources you can use (much like a resource pool).
When you enabled the Workload Management components, you created a special Kubernetes cluster called the "Supervisor Cluster". You can continue to deploy virtual machines in this cluster, and you can also deploy kubernetes pods as a "pod vm" which is basically a container with some special wrapping so they are better isolated, like a virtual machine is.