You Do Need power plug adapter while traveling from India to Iceland.

Here is Why You Need An Adapter

The outlet and plug type used in Iceland are C and F and in India are C, D and M. This is how they look like.

India

In India, outlets of type C, D and M are in use.

Type C

Type D

Type M

Iceland

In Iceland, outlets of type C and F are in use.

Type C

Type F