Dogs can eat a lot of human foods that we eat and they do not have to have dog food to survive.
Dog food was not always around when dogs were needing to eat so they had to rely on a lot of foods that humans eat such as meat.
You can feed your dog some cooked chicken, vegetables, rice etc.
However I would still recommend feeding the dog some good nutritious dog food to keep them healthy because too much human food could cause the dog to be overweight.
And actually it's cheaper to feed your dog some dog food at least part of the time because human food really is more expensive than dog food when you think about it.
But if you can afford it and want to feed your dog only human food then you can do so.
A lot of dog food has human food mixed in with it such as chicken and other vegetables.