We can convert our sales order data to Invoice data by using custom button "Convert Sales Order to Invoice". Custom button "Convert Sales Order to Invoice" is available in every sales order in the Sales Order module. We can convert our data from one module to another module using the custom button by, which can achieve by applying some of the function on data. It will provide the facilities to convert our data and applied some condition on data as per our requirement.
If you want to convert any data from Sale Order to Invoice. Just open that data and clicked on custom button "Convert Sales Order to Invoice" from the top right menu.