I am planning to change my general physician. While searching I notice two types: 'family medicine' and 'family practice'. What is the difference?

Not much difference! Family medicine and family practice doctors are the same. These are the doctors who specialize in you! they provide comprehensive care across the life span from infancy through old age. Many deliver babies! they are able to take care of about 90% of the problems that a person needs to see a doctor for. They provide care in the context of your biological, social and psychological situation.
No difference. You say tomato I say tomaaato .