If its a breeder that its been sold to 6 weeks at the least if its a normal person at least 8 weeks.
Never give an animal human medicine unless a veterinarian prescribes it specifically. It can kill it. Ask a vet what to give the puppy.
a puppy needs to be a least 2 years old to mate it has to be at least 4 years of age
If properly weaned, 6 to 8 weeks.
I work as a Vet Tech in WA state. You should wait 2 weeks after your puppies last set of vaccines to put your puppy in a kennel, they can get kennel cough, distemper, parvo and other awful diseases...