Over heating 2003 4runner

I have a 2003 4runner V6. Car overheats at idle however when I drive it cools down until I am stopped or at idle then it will creep back up. Boiling coolant in the reservoir after car is off. It doesn't really happen in the winter months. However in the winter months the heater will only blow heat when I'm driving and not at idle. I do have to add coolant but I suspect its being pushed out the coolant reservoir. I dont have any codes for misfires.

Thermostat with housing, water pump and new radiator cap was replaced in 2022. Could it be a faulty thermostat or blown head gasket?