A.
Yes. As with any inbuilt fridge please fit strictly as per the instruction/installation manual. It is particularly important to ensure that any specified ventilation points are used otherwise the fridge may overheat, operate improperly or suffer premature wear.
Your battery may be suitable, but it depends what other load there is on the battery (ie what other items are running off the battery also) and how it is being charged (solar panel & size or other energy source?, what type regulator is being used?) We would need more details to assist better.
Regards
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