Custom controls have to be added to qgroundcontrol for camera movement and zoom. All the details are added in the attached presentation file. We can discuss the details over a meet.
Repo - [login to view URL]
Project details - [login to view URL]!AtxS7eQd6P3pi1ed1qRux5mD2oF8?e=Y5E6R5
Code for similar controls using a widget - [login to view URL]