How do creatures with creature controllers work?

How does using creatures work with creature controller? It seems to me that most of the perk commands give the creature a readied action like with the Attack command. It can’t actually attack when the command is issued. But then when it is activated it has to do the readied command first which means it can’t move into close combat to do the attack action. Does the creature have stay within command range or can it start in command range then move out and still perform actions? Does the creature get it’s regular turn without being given commands by the controller?