Kenmore Side by Side, Fridge not working, freezer is

I am not sure of the age of the fridge, it was in the house when we moved in. I noticed today that the fridge is not as cold as it should be. The bottom of it where the vent comes in from the freezer is cold then the top. I can hear the water wanting to be dispensed into the ice maker but it is not making ice. I have cleaned the underneath to the best of my ability, but am afraid to mess something up. I donot know what is wrong.