Breeding started when dogs and people lived together for the first time. “How did the playback start?” To answer your question. for more dogs you simply need to distinguish between breeding and selective breeding for certain traits.
The first people knew nothing about genetics, but they were observers. It was easy enough to tell when a dog was hunting and doing the other. This dog may have taken extra food to pass on its genes to future generations. This was the best as a casual fussy. The dogs that completed this lifestyle survived and grew up.
This early breeding was important for the breeding of companion dogs. The survivors have learned to look for food, security and compassion for people. A dog follows a person to find out what to do and a wolf tries to find something for himself. It’s not something a dog learns, but something he learns instead.
Dogs have changed while people’s lives have changed. Farmers, shepherds and hunters needed special qualities that they used to do their jobs in dogs. A hunting dog is a bad substitute for a shepherd dog. At this stage, there were species of basic dogs but no particular breed. Even the looks had little importance. The dog was used to create more puppies that would have been better and perhaps better than their parents, provided they were good at the task.