Most of the time when you 'get started on K8s', you get started by using a cluster that's setup by a provider of some sort - be it a cloud provider, a platform

Most of the time when you 'get started on K8s', you get started by using a cluster that's setup by a provider of some sort - be it a cloud provider, a platform team in your company, or some prebundled bare metal Kubernetes distribution like K3s. In these cases, a you will most likely already be provided with, or at least recommended an Ingress Controller. Setting up K8s clusters from scratch on bare metal (or even worse, VMs) is generally not something you should be doing, unless you really know what you're doing and have a good reason to. Think: going 'Linux from Scratch' instead of installing Ubuntu. K3s is not an alternative to K8s, it really just is a distribution for bare metal deployments. So is Rancher, OpenShift, etc.