How can you train what if your dog not to go potty inside?

No wonder the dog is confused! You let the dog go out to do it's business and then YOU clean up the mess. It's no different than telling your child to use the washroom, but not the toilet! If you are tired of cleaning up poop in the backyard then make a doggie run on part of the property out of good stiff chicken wire. I've done that and my dogs have a place to go without dirtying up the backyard (that's their play area) and cleaning up a doggy run is far quicker and it should be cleaned up every second day.