@VeeraragavanJ , I'm currently looking for an updated answer to this, too. However, several years ago in Pega 6 I wrote a funny little component to display a text box in a modal dialog into which the user pastes values copied from Excel (header included). A very generic process then populates a page list. It then refreshed the grid to display the "paste".
There was even an option to use a data transform to consume denormalized data to create multiple objects with lists populated. It was very klunky compared to just pasting into the grid, but it was widely used across the company.