How to set up the Rbac in Aks

Kubernetes
#1
  1. In rback resource yaml file should i mention the user name ?
    if i mention the username and apply that , does aks recognize that gmail login by then
    2.if the user is not present in the yaml file configuration then which previllages he gets.
    if possible can you provide the steps how implement from in the cloud and in yaml files with screenshots or photos ?
#2

Are you following along on a particular lab or lecture here? A link would be helpful.