A Chapter/Module/Unit inside book can be added in multiple ways, upload a file upload or web link or create content.
Click on button on the edit content of Qstore book dashboard in Manage Chapter/Module/Unit section on right side of the screen.
Click on button on the edit content of Qstore book dashboard in Manage Chapter/Module/Unit section on right side of the screen to upload multiple files together.
Enter Chapter/Module/Unit name in the pop-up screen.