My Dog Attacks Me When I Punish Him, What Should I Do?(extra Details For My Last Question)?

i have a two year old cockapoo and he attacks me when i punish him. he is a dominant male that is fixed. he has a potty training problem, ive worked with him since he was eight weeks old and he is still not housebroken. he is crate trained. i correct him by either smacking him on the butt or yelling at him(verbal commands, bad dog ect.) i havent let him get away with much without a punishment. he attacks any dog in sight and doesnt like little children. his attacking has gotten soo bad that i took him back to the breeder for advice. she told me when he attacks me i should grab him by the scruff and put him on his back until he calms down. ive tried this but after he calms down and i let go he attacks me again. he can be a nice dog sometimes. ive taken him to the vet and there are no health causes. please help!!!

(dog Potty Training – See Details) We Have Two Girl Cockerspainel/poodles (cockapoos) And We Have Tried To…

…potty train them but it didnt work. We are forced to keep them outside in a pen that we built because we already had to replace the carpet in my children`s playroom. Any ideas on how to potty train them? We can start using the garage (it has a rug) and then once they master that, move into the house. Ideas?