+1 to what Craig said. Good idea to slow down a bit and think about what the power needs are will ensure you build a system that works well the first time. The 3A draw from the fridge is a good starting point. That's about what mine uses, and it runs about 40% of the time in 80*F heat. 3A * 24 hours in a day = about 75AH a day, but it is only running 40% of the time, so 75*.4 = 30AH
If you are building a LiFePo4 based system, a 100AH battery would be good for 3 days (30AH *3 days = 90AH) without charging and no other loads. Two days would be easy. So you are parked in the shade for two hot sunny days, and that you need to recharge fully on day 3. That means recharging 3 days worth... 90AH on day 3. That's 10A of charge for 9 hours, or some other combo to get 90AH.
If you have 120W of solar panels, they will give you roughly 10A (more like 8A) in ideal sunny conditions (120W = 12V * 10A). But will you get 9 hours of sunshine? Not likely. So, aim for 2x that, or a 240W solar suitcase.
Practically, I would have my solar panels in the sun somehow, so that they are charging at least part of the day, and I don't end up just drawing power but also putting some power back into the batteries.
For reference, I have about at 55-65AH daily draw, 200AH of LiFePo4 batteries, and 330W of solar. That works well for us, unless we are using the Induction cook top a lot, and then I need to drive as well to charge up the batteries.