The endothermic process is a term that describes a reaction where the system absorbs the energy from its surrounding in the form of heat. A few examples of the endothermic process are photosynthesis, evaporating liquids, melting ice, dry ice, alkane cracking, thermal decomposition, ammonium chloride in water and much more.
CaCO3(s) ---> CaO(s) + CO2(g)
2H2O(g) ----> 2h2(g) + O2(g)