Follow the upper radiator hose to engine compartment, the thermostat will be located there inside the thermostat housing. with the right knowledge and tools yes you can replace it yourself. some steps are below to help you along the way
1.Disconnect the negative battery cable.
2.Drain the cooling system to a level below the thermostat.
3.Disconnect the coolant recovery system hose from the thermostat housing.
4.If necessary, you can unfasten the upper radiator hose clamp, then slide the hose off the fitting.
5.Unfasten the thermostat/engine outlet housing connector bolts, then remove the housing. Remove the thermostat from the engine.
6.Remove the O-ring, then thoroughly clean the sealing surfaces.
Note that the vent should face up (see arrow) when installing the thermostat