Size is not always relevant when it comes to how much energy and exercise a dog requires. Others require only a few minutes of going over with a brush once a week as well as regular attention to teeth, ears and nails. All dogs shed to some extent. Even supposed no shed breeds will lose hair. Hair falls out of follicles take a look at your own brush or how often do you pluck a strand off your jacket.
Some breeds shed less than others.
If you are a neat freak and cannot stand dust bunnies, consider a lower shedding breed. Also, coat length does not mean a breed will shed more or less. Again, you must research the breed or cross in regards to what you want. If you want a dog that can be trained for duck hunting a Collie may not be the right breed. There are many breeds that are not appropriate for a novice for one reason or another.