@er-khushboo27,
You can show indexlabels to the top most dataseries of each stacked column by setting indexLabelPlacement property to “outside”. Please take a look at this updated JSFiddle for a working example.

If this doesn’t fulfill your requirements, can you kindly brief us more along with an example or a pictorial representation of your requirements so that we can understand it better and help you out?
—-
Manoj Mohan
Team CanvasJS