I want to shoot my dog because he keeps pissing in the front yard.
Why would even think of doing such a thing to your dog?
Because he has done this multiple times already.
Peeing in the front yard seems like where you should want your dog to use the bathroom. Even if it's not though, shooting your dog because of that is not an appropriate response. As a pet owner, you are suppose to take care of your pet and raise them responsibly.
It's fine. I can't stand this dog anymore and if he won't change, I might as well shoot him.
Pets go potty outside and if he is escaping your back yard you should get a fence. It would be better to surrender your pet the a rescue or a shelter and they can re home them.