i could explain the wo8 :20
from the formula or the name u could tell that the reactants are C6H5CH2CO2H and C2H5OH
so the phynyle bromine needs to add 1 carbon atom by nucleophicilic addition with CN- ions then converted to an acid by reaction with dtrong acid , the resulting carboxilic acid is reacted with C2H5OH to produce ester.
hope i helped