To create a choropleth map in an Interactive Map visual, you must specify a choropleth Layer ID.
To create a choropleth map in an Interactive Map visual, you need a Custom Mapbox style and a Layer ID.
When you request for a custom style from Mapbox, make sure that this style has a choropleth shape file in it. This shape file has the choropleth Layer ID, which is the name of a unique layer within the Custom Mapbox style that identifies the shapes that you would like to color by a measure in your data. See Custom mapbox style.
To specify a layer ID, navigate to the Choropleth menu under Settings, and enter a choropleth layer ID in the Layer ID text box.
Proceed to Creating Choropleth Interactive Map Visuals.