btw- don't feed a puppy human food. it's not good for them and it makes it tougher to train them.
That is absolutely not true. The right human food, in the right quantities, is better for your dog than any kibble you could feed. The difficulty lies in knowing how much of what to feed.
The
type of food you give a dog has no effect on how difficult it is to train them. Only
when you feed - following which behaviour. If your dog begs at the dinner table and you give him a piece of boiled chicken, then yes, he will be more badly behaved and continue to make a nuisance of himself at the table. If your dog begs at the table and if you give him some kibble, he'll be just as poorly-behaved.
And I do think that feeding a dog nothing but chicken and rice is ridiculous, and absolutely horrible for a dog's health. I would rather have my dogs on Purina than on a diet comprised solely of chicken and rice.
To the OP: If you want to feed your dog "people food", do it right. Read about homecooked or raw diets. Learn about how to balance the different nutritional requirements of your dog's body. It's not just about throwing together a meal... dogs have different needs than humans. They need the right amounts of protein, calcium and numerous other things.
If you don't plan on feeding your dog "people food", that's fine too. The first thing I would do is upgrade your kibble. Purina is a pretty horrible food... very little nutritional value, generally speaking. Look for brands like Wellness, Natural Balance, Solid Gold, Taste of the Wild, Innova, Chicken Soup and Orijen.
Secondly, don't spoil your dog. Put down the food for 15 minutes -- if she doesn't finish it, take it back up. The food should be plain, or however you intend to serve it in the long-term. Put it down again a few hours later for 15 minutes -- if she doesn't finish again, take it back up. She should get NO treats in between meals, nothing to eat at all. A healthy dog will not starve itself... a healthy dog can go several days without any food at all.