Running a fridge off 12V?

I'm about to be homeless so I'm looking to get a small refrigerator in my Honda Civic. I see they make 12V refrigerators, but what should I do about my electrical system? The refrigerator needs to be ran 24/7, so it will drain my battery. Should I get a few of those deep cycle batteries? Can I keep them charged by paralleling them to my stock battery? Is my alternator gonna be able to power all that?

And what do I need to look for to make sure I won't run out of power? Watts for the fridge & Kw/hrs for the batteries?

***Millennial with student debt.

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