For domestic invoice the buyer ans seller is enough but for export invoice we have to add additional column notify party,How to do this ?
what exactly do you mean by “notify party” ? some visual example would help users understand your query.
if by “notify party” you mean the concerned person who should be informed about the shipment, then such information can be added as a custom field and positioned on the invoice as per choice with a custom theme.
you can also add the same as a custom field for the customer, and it will be displayed along with the other custom fields or you can display it below or beside the customer details in your invoice with a custom theme.