If your dog or puppy is going to be a pet and family companion, having her/him spayed or neutered will insure no unwanted pregnancies will occur. Research has shown that it is best to allow your dog or pup to go through puberty before having sexual alteration done, but your municipal laws may require it to be done earlier. Click here for research information.
Health risks are lower for dogs neutered/spayed at 1 year or older.
Breeding is WORK and should not be entered into lightly or with lack of knowledge. Just as you would not want to give birth to a child without the help of someone who knows how to handle complications, you should not expect any less for your bitch. Most births happen normally, but as in any mammal birth, problems can arise that may require the bitch to need help or possibly a C-section. You need to know how to tell if your bitch and/or her pups are in distress so you don't end up losing one or both. Most breeders are on hand to observe and help if needed for each and very litter born.
The next 8 weeks, or more, are spent cleaning kennels, worming, vaccinating, weighing, feeding, weaning, evaluating, and socializing puppies. It's spent making sure all your puppies are getting enough nursing time and your smaller ones are not being pushed out by bigger ones. If your bitch doesn't produce milk, or produces less than her pups need, you will be bottle feeding.
You also have paperwork. Registration papers, health records, pedigrees, etc. You also have to screen buyers and answer questions. It takes time, money, and hard work to raise puppies properly and should not be done on a whim or by accident.