Soft Dog Cat Crate The Portable 2-in-1 Double Travel Kennel Tube Carrier for All Pets Car Seat Ready

Can the two compartments be used separately as well as togetger. If so with they have all sides enclosed?

I have an American Bully who's weight is 55 pounds..will it work for him?

What are the dimensions?

The space I have available is approx 2-3 in. smaller than the width of these (Trying to fit them next to a carseat). Could they squish a bit to fit?