The cold control is behind the knob you turn to adjust the temperature.You will need the manufactures number to order parts.
I would check for leaky door gaskets and the jelly roll condenser in the back for a lint clog. If ok,your refrigeration system is running inefficiently, either a bad condensing fan, inefficient compressor, or refrigerant leak. If the jelly roll condenser is not hot, that would confirm one of the above. For equal energy transfer, that condenser should be too hot to touch, like 140 degrees. For average electric rates, you are probably wasting $ 100 a month on this. Best to get it fixed soon. A new fridg uses about 1/2 the energy as this old R12 fridg uses.