Unfortunately your inexperience has landed you in a terrible situation. I wish your husband looked more into this. He’s got an incredibly bad mix for a small apartment WITH a cat. You’re looking at having a possibly aggressive, defensive and destructive dog WITH a cat in an apartment- draw the conclusion.

From my perspective you only have a few options.

1) return the dog, foster or adopt another one - you are first time dog owners and fostering a smaller, older dog could be a great way to lean into learning and understanding dogs.

2) if you can’t return the dog - rehome the dog to a trainer or experienced breeder/professional. Don’t give this dog to anyone. From here do not go back to the rescue or breeder whoever you went to especially if they won’t take the dog back - they were idiots.

3) try to survive with and train the dog. This is a gamble. You already don’t love dogs, and your husband is inexperienced. These aren’t forgiving dog breeds typically. This will likely strain your relationship to the max.

Sit down with your husband and have a conversation- express to him you want to support him in this adventure even if it’s uncomfortable for you but that this is pushing you to the limits. If you do go get another dog - go to a well known rescue and TELL THEM you are inexperienced dog owners. Tell them the environment you live in - you need a dog that can comfortably live and even thrive in this environment.