Question

What do you understand by "all the world's a stage
and all men and women are merely players"?
from The Seven Ages by William Shakespeare

Answer 1

All the men and women in this world are mere actors on the stage of life. After taking birth in this world they enact several roles starting right from infancy to the last age of sensibility. then they gift the stage which means they die and the drama of their lives come to an end

Answer 2

This line indicate that we are all part of a play. Our life is the start of the play and the death end. We all take birth and play our part on this world's stage and die. So we all are the player and our life is divided in several parts of play.
Hope the answer was useful.