Whirlpool Frig. Frig quits cooling on its own! Everything melts, etc.; we then have to maually

Question

Frig quits cooling on its own! Everything melts, etc.; we then have to maually switch it off and then back on for it to cool properly, but then it repeats! Thermostat? Where to locate in whirlpool upright frig (approx 8 yrs old); Can we fix it ourselves? Thanx, C