When you first get a new puppy, you can not expect the dog to be used to walking on a leash or even having a collar on. It should be done in a step by step process. If you force the dog to try and walk then they will fear the collar and that can cause problems for the future.
First thing you need to do is put the collar on the dog. Even if they are scratching at their neck, it is totally normal because they are not used to having something around their neck. Once they are used to the collar then you can get them used to the leash.
Do not put the leash on the dog and always expect the dog to be excited to walk with you. Most puppies will just lay down and refuse to walk. The best thing to do is to put the leash on the dog inside the house and let the dog walk around with it while you are home, so they get used to having the leash dragging behind them. After about 2 days, then you can try taking the dog for a walk.
Once you try taking the dog for a walk, grab a squeeky toy to get the dog excited. Start walking with the dog on the leash while squeeking the toy and telling the dog to come. As soon as the dog starts walking with you, give the dog plenty of praise, “good girl or boy come on.” Do it for a short amount of time the first time and progressively get longer each additional time. Once your dog starts walking you will be able to enjoy a long walk with your dog. Just Be Patient!!!!