Will BISSA Shoe cabinet with 3 compartments, white, 19 1/4x11x53 1/8 " fit in an Alfa Romeo Giulietta 2017?

The Giulietta gives you a short, wide load bay rather than a deep one. The opening measures 35⅜″ wide by 29⅞″ tall, and behind it the floor runs only 29⅞″ with the seats up while the narrowest point across is 40⅛″. Fold the rear bench and the floor stretches to 57⅞″, a gain of 28″, which is where this boot does its real work. It takes stacked boxes and soft bags well, long flat cartons badly. The sill sits at 30⅜″ with an 8¼″ drop, so slide loads in and lower them rather than dropping them.

BISSA ships as a single flat box, 54¼″ × 16¾″ × 3″, and it weighs 45 lb 15 oz. At 3″ thick it slides into gaps a built cabinet never would, so the thickness is not your problem. The length is. At 54¼″ you need a trunk that measures long enough on the floor, or one rear seat folded so the box can run forward between the seats. Most hatchbacks take it with the seats down, and any wagon or SUV swallows it flat. Lift it on edge with two hands, and rest it on a long edge rather than a corner, because 45 lb 15 oz of flat pack lands hard and the corners split first.