Question

evapouration is known as surface phenomenon

Answer 1

Evaporation only occurs at the surface of the liquid as the molecules at the surface gain energy and evaporate but boiling occurs throughout the liquid.

Answer 2

Process of evaporation is the escaping of molecules from the surface into the atmosphere /space above the liquid, at any temperature.  Usually the entire liquid is at the same temperature in this process. Evaporation is  slow and continuous.

So evaporation occurs only from the surface of the liquid.

Boiling is the processing that stirs the entire volume of liquid boils, moves due to convective currents.  So the entire volume of liquid is subjected to boiling.