My goodness, where do i start?
First of all, of course you won't breed until they are both 2 years old, because OFA certification cannot be done until then. I'm sure you don't want to breed and produce unhealthy puppies.
Next, I want to ask you a simple question:
IF you breed your dogs, and should you get a nice sized litter, let's say 10 puppies. (not uncommon in Newfies).
Now let's say you spend the first week or so with the bitch and take flawless care of the puppies. You tag and ID each one like good breeders do, and keep records of how they behave. You have all the health care done, and feed them the best food.
Now when they get to be 4-5 weeks old, you are going to call up the local pet store, and sell them 4 or 5 of the puppies so that they can put them in window cages, and sell them to anyone who has the cash, right? No screening, no contract, just anyone who has the money to buy them. Right?
No? You don't want to do that?
Well, I don't blame you. But that is what happened with YOUR puppies. NO BREEDER who has ANY care whatsoever about what happens to their puppies will sell any puppy for resale.
I would DROWN my babies myself before I would EVER sell them to anyone for resale.
It is absolutely CERTAIN that your dogs came from commercial or high risk breeders who either do not understand how to breed dogs, or do not care.
I guarantee you your dogs should not be bred.
Breeding can be hard. Many if not most times, in addition to being about the miracle of life, it's also about the miracle of death.
Puppies can die, bitches can die, and/or they can all die. Complications can be difficult and expensive. You can be left with a grieving bitch with no puppies, or 10 puppies to feed and clean every 3 hours around the clock and no mommy dog to help.
Breeding should be well thought out, and people should plan to spend at least several YEARS educating themselves in their chosen breed before considering breeding from the very BEST animals they are able to purchase.
If you are DETERMINED to breed, your bitch should be carefully evaluated by people in the know in Newfs so that you can figure out what her faults (all dogs have them, some more than others) and virtues are.
At the very least, you should send her to a CH dog, and not just the dog who happens to be standing in your yard.
I urge you to CAREFULLY CONSIDER and then REconsider the wisdom of breeding your 2 dogs who came from the pet store.
Most people really do not like to hear that their dogs are likely not suitable for breeding, and that breeding them would be irresponsible, but the vast majority of dogs should NOT be bred.
Breeding carries with is such a weight of responsibility for me that it is almost impossible to describe.
EACH breeding has an effect on your breed for eternity. You are adding to the gene pool. It pays to think very carefully before proceeding.