Question

displacement can be zero or not?

Answer 1

yes it can be zero if it comes back to the same place after completing it's path

Answer 2

It can be zero.

First look at definition of displacement.
Displacement: Shortest distance from initial and final point.

Displacement is zero if you started moving from a point and ended at the same point.
E.g. Your displacement is zero when come back to Home from college. Starting point and end point is same i.e Home.