Maintain sales document item category

Here, you can assign item type and main partner function (e.g. ship-to party) to a combination of sales order type and item category.
Indicators for tax laws as well as for statistical calculation of taxes ICMS and IPI can also be assigned.

Further notes

Please make sure the entries for main partner functions are consistent with the settings for the appropriate billing type.

See customizing menu

"Billing Document Type".