Elections are a democratic way of selecting representatives.
They ensure that the representatives rule as per the wishes of the people.
Elections help voters to choose representatives who will make laws for them, form the government and take major decisions.
The voters can choose the party whose policies will guide the government and law making.
Thus election is a mechanism by which people can choose their representatives at regular intervals and change them if they wish to.
This is an important question for cbse class 9 as well as 10. You can also seek your ncert political science book chapter electoral politics of class 9th. I am a 9th grader, that's why I know.