Which of the following is a viable solution for getting a total on top of a Stacked Column chart in PowerPoint, so that the total value automatically updates as the underlying numbers of your chart change?

Use the Calculate Total option for your Stacked Column chart, so that PowerPoint adds the totals automatically to your chart.

Add text boxes to your Stacked Column chart, then link those text boxes to the totals you calculate in your chart$$s underlying Excel spreadsheet.

Chart the totals as its own unique series, use its data labels for the totals of your Stacked Column chart, hide the series using No Fill and No Outline formatting, and then adjust your Y$-$axis as necessary.

Chart the totals as a Clustered Column chart, push that series onto the secondary axis, use its data labels as the totals for your Stacked Column chart, then hide the series by setting its Series Overlap to $0\%.$