Question

in a process on a system inital pressure and volume is equal to final pressure and volume

Answer 1

The statement that equal initial and final pressure and volume implies zero work is false, since work can be nonzero in a cyclic process.

Answer 2

If the initial pressure and volume equal the final pressure and volume, the system has undergone a cyclic process. In a cyclic process, even though the state variables return to their initial values, the work done (given by the area enclosed in the PV diagram) can be nonzero.