Unable to give draw balloon on DWG file using Autodesk Viewer

We are attempting to create a balloon on a DWG file but are unsure how to do so in Autodesk Viewer. Could you possibly offer a solution or do you have any resources for this in the Autodesk team?

Also, how to get callout API on the normal Autodesk Viewer?

We are referring circle as a balloons which consists of numbers!

We implemented callouts in Autodesk Construction Cloud, but we couldn't find a way to convert a rectangle of callouts to a circle (Balloons).

First of all, when we're viewing a drawing with Viewer, we're actually viewing a non-modifieble translation of the original desing.

You can find the detailed process at https://aps.autodesk.com/en/docs/model-derivative/v2/tutorials/prep-file4viewer/

From there, you have two options:

1. Modify the source file and prepare the new version for Viewer
2. Add the ballon and callouts to the model scene

For option 1 you'll need to use Design Automation API for AutoCAD. You can refer to the documentation

For option 2 you can add SVG to the scene, take advantage markupcore extensions or integrate your custom markup