Hello,
It depends where you want to add the new data – local or server side. Inpriciple to clone(copy) row you can use method to get the selected rows and add it to the grid – see methods getRowData and addRowData see docs here
After you add the rows with certain ids(see addRowData) you can simple call the form method to edit them.
Since your explanation is very common, I can give you a common answer in principle.
Kind Regards,
Will