How to train a puppy?

I have an 8 week old female Golden Retriever puppy that is either very hyper or asleep. I tried to train her to sit and even tried calling her by her name. I looked up almost every way to train your dog to sit. My puppy is just not interested in the treats I give her. I tried giving her different types of treats and it all ended the same- I give her the treat when she does the trick right, and she doesn't eat it. I tried giving her a favorite toy, and even praising her, but I do not think the point gets across to her. I have no idea how to work and train her. Is she to young to start training? Is there any other kind of way to reward or train her?