unable to add or modify the chart title when using continuous fields.

Hi Ansar,

With continuous fields, Tableau creates an axis rather than a discrete header. You can still customize the title by right-clicking/double-clicking the axis and selecting Edit Axis, then changing the text in the Title field.

If you're referring to the worksheet/chart title at the top of the visualization, that can also be edited independently through Edit Title. Tableau supports editing worksheet titles regardless of whether the fields in the view are continuous or discrete. 

So you don't necessarily need to convert the continuous field to discrete just to change the title. If you're unable to see the Edit Axis or Edit Title option in Tableau Next specifically, please share a screenshot of the visualization and the options you're seeing, as the Tableau Next interface may differ from Tableau Desktop/Cloud.