Hi, I am very much new to kubernetes and trialing out the DO managed kubernetes product and have some questions that i need help with - struggling to find clear guides/docs describing the following:

Autoscaling

• What is the difference between using kubectl autoscale... and doctl kubernetes cluster node-pool ... (or via the dashboard) to configure autoscaling? Do they have the same effect?
• What confuses me is the kubectl allows for the –cpu-percent parameter which determines when the pods scale up, but it is not clear what controls doctl…

Docker images

• Is it possible to build & deploy a docker image directly to kubernetes without needing to use a registry such as dockerhub?

Security:

• Network
  • Firewall: firewall was created by default with the cluster, but not much detail on what exactly it is filtering?
  • My interpretation of the rules are that it blocks all traffic to the cluster except on ports: 30000-32767 is that correct?

Context on my environment:

• Load balancer
• Cluster
  • Express Node web api
  • one node with two pods
• Managed Postgresdb