If he's an older dog, he's probably used to his name; however, changing it isn't out of the question. If he's from a shelter, they may neglect to tell you that he has a temporary name assigned to him by staff. If he's from a breeder, he'll come to you with a long name, which you may want to shorten, or change. And if he's coming out of an abusive situation, a new name may represent a fresh start. But we're lucky: dogs are extremely adaptable. And soon enough, if you use it consistently, he will respond to his new name.
In competition obedience training, “heel” means the dog is walking on your left side with his head even with your knee while you hold the leash loosely. Puppy training can be a little more relaxed with the goal being that they walk politely on a loose leash without pulling. Some trainers prefer to say “let’s go” or “forward” instead of “heel” when they train this easy way of walking together.
First, teach the release word. Choose which word you will use, such as “OK” or “free.” Stand with your puppy in a sit or a stand, toss a treat on the floor, and say your word as he steps forward to get the treat. Repeat this a couple of times until you can say the word first and then toss the treat AFTER he begins to move. This teaches the dog that the release cue means to move your feet.
Imagine your puppy running out the front door. You call him, waving a treat. But he'd rather chase a squirrel into the road than come back to munch on a treat. In addition to the obvious danger of Puppy getting hit by a car, he learns that he doesn't have to listen to you. He learns that he's in charge of what he decides to do and what he decides not to do.