How do I fix my fridge that is not refrigerating?
Assuming someone didn't screw around with the refrigerator's thermostat or temperature setting...
Typically, that problem is due to failure of the circulating fan housed in the freezer...thermostats almost never fail. Hopefully, you notice there is no or very little noise being made by the refrigerator when you open the freezer.
It doesn't matter how cold the freezer is if the refrigerator isn't cold. There shouldn't be silence unless and until the refrigerator's desired temperature is reached.