The approaches to raising dogs of any size are identical. Train a small dog the same way you would train a large one. You would not want a Great Dane to jump up on your guests, so do not tolerate this behavior in a Lhasa Apso. You would not train a German Shepherd to void on newspaper, so take your Yorkshire Terrier out for at least 2 walks every day. While most dogs enjoy playing with people, cats can generally amuse themselves.
Most cats enjoy interacting with their owners but are often content to play alone.
Cats do not need to be let outdoors to live a happy and healthy life. In fact, they are better off remaining exclusively indoors. They may adapt better to smaller homes or apartments than do some dogs. Cats do not need to be walked, though a cat can learn to walk on a leash. Though their activities can be more solitary, cats thrive on attention and social contact with their owners.