All toddlers say no and push the boundaries. Bst to keep it short and simple . Give maybe two warnings but no longer than 5 minutes as lo's have no real concept of time and will get distracted. Also to avoid confusion use only one step instructions , so "it's bedtime now" or "let's go inside" otherwise he'll only hear half of it. Then follow through, if you don't or allow extra time in response to whinging and him delaying, he won't take you seriously next time and will learn he can change your mind. If he makes a fuss don't make eye contact or discuss it, tell him what you are going to do and go through the motions until he calms down.