Hello Tina.
Caravans are usually tight on space, so if you need to replace an existing fridge in your caravan I suspect you may have difficulty in finding one that will fit the existing space. But if you can find one that fits, then it is possible. You also need to be aware that many caravan fridges have to be shaped at the back to make way for wheel arches, or other obstructions which could prevent a normal domestic fridge being pushed fully back into place.
However you may also need to consider some of the other differences, which might affect your decision.- touring caravans usually use fridges that can run on mains 230V ac power , gas or 12V dc from the car.
If you only use sites with mains hook up, then again a normal domestic fridge may work, but you won't be able to keep it running whilst you tow the caravan as it won't work on 12 V from the car. If you ever use a site without a mains supply, a domestic fridge will not work.
And there is another important difference between caravan an domestic fridges, domestic fridges use an electric compressor, which although generally are very quiet and in a normal domestic setting of a kitchen is unlikely to annoy you, but in a caravan , which is made of lightweight materials which can act like the sound box of a musical instrument, even the slight noise and vibration of the compressor running may become apparently much louder and thus disturbing. Caravan fridges do not use a compressor, they use a different refrigeration method called absorption, this is near silent.
I hope this may inform you of some of the reasons why caravans do not use normal domestic fridges, but if you are prepared to not keep your fridge cooling during your periods of towing, and you always use a site with mains electricity, and you are prepared for the possible noise of of a compressor fridge, then it could work for you.
Just a further note, compressor fridges have more effective cooling than caravan fridges.