practicing IAM service and I don’t have permission to create a new user and give him permissions within the root user given in the AWS playground
This is by design. If you could do that, you could commit to more or less unlimited charges. So it’s a cost and security problem; our playground can not support this.
You should be able to create a user so long as the name of the user begins with iamuser_
What permissions you can assign to it are governed by policy. It cannot have more permission than the kk_labs user you start out as.