Homeostasis is very important and your body function or the enzymes here because of your body being in homeostasis. If increase or decrease in temp, your body will halt all processes and try to readjust your body back to normal first because if not, then a lot of other processes would be affected negatively as well and you could potentially get ill.
Answer: Thermal energy from the fire moves to the water in the form of heat.
Because according to second law of thermodynamic, heat flows from higher to lower temperature region. Heat is the transfer of energy from an object at higher temperature to an object at a lower temperature. so energy flows from warmer to colder objects