My puppies were born on the 17th of sept and have fleas really bad. I want to know when I can use a flea shampoo on them.

See
https://www.askmehelpdesk.com/dogs/puppies-fleas-102851.html

https://www.askmehelpdesk.com/dogs/fleas-newborn-puppies-102646.html

https://www.askmehelpdesk.com/dogs/fleas-puppies-114152.html

https://www.askmehelpdesk.com/dogs/3-week-old-puppies-have-fleas-115471.html

I really find it upsetting that so many people are so irresponsible about breeding dogs. Those unwilling to make the major commitment doing breeding right, should spay/neuter their pets by 6 months.

They should be 6 weeks old now and you can use effective things such as Revolution on them.

Good advice but this should be in dogs not zoology.