Where you live (climate / town or country), what kind of building (garden / stairs),activity level / exercise (yours and the dogs) type of coat (grooming), size of dog, male or female etc etc
Researching the breeds and then speaking to as many responsible owners as you can will give you a real insight into the numerous breeds of dog, as no single breed of dog is suitable for everyone.
One thing though that all dogs have in common is instinct or as Wikipedia put it, the inherent inclination of a living organism toward a particular complex behavior.
My advice, stick with this blog, it’s not half as taxing on the brain
Some breeds have more instincts than others, depending on what the original function the dog was bred for, whether it was to guard, hunt, herd etc, dogs like border collies or greyhounds still have the basic instinct that the first members of their breed had when the breed was originally founded.
Most dogs have the instinct to dig, some more then others (I know I have four standard smooth dachshunds) and most male dogs like to mark their territory when out for a walk, an instinct that goes back to wolves and the earliest canines.
Some breeds have a higher prey drive than others, which should be a major consideration when deciding on choosing a breed of dog to live with your family, and others are known to be more protective of people and property, again going back to before dogs were domesticated when they had to guard their territory from other packs or threats.
That’s an awful lot of information to take in, but it’s in yours and the dog from the breed you finally decide on interest, to make the right decision first time as a bit of time spent in the planning stages should ensure that the next 10 + years will be a mutually rewarding experience for you and your dog.