Okay so about 8 months ago I moved into an apartment and I have both a dog and a cat..my dog is use to being inside all day but the cat is use to being outside because of the house I lived in. Well I was outside smoking a bowl and I heard my dog whelped and I walked inside and seen my cat stright attacking the *****..they have fought once before which was like the first time ever they've fought like that.
Put them down with either a blunt object such as a tire iron or Crowbar and Wooden Baseball Bat with Nails in through the end. Or my favourite method a syringe with an air bubble in it or a more humane way some kind of heavy dose of narcotics idk not Vet here ya could just bring them to the vet but they are kind of pusssy when it comes to situations like this but yeah you probably wanna keep one pet or just kill both oh and a shotgun to the face or any firearm even explosives will work although messy sooo do not do it at home lol loud shit too wear ear plugs.
They're probably have a shit load of energy to burn. Also your cat is going to get fat as fuck, so put its food in a high place where it has to jump to get it. And please walk your dog at least every other day, they really need exercise.
Exercise. Walk the dog daily, play with the cat daily. It will help burn of extra energy and keep them even keel.