How does Reg- Master Planning - Group by items permit the identical item to be addressed as a single item on a single purchase/sales order?

Hi everybody, My requirement is to arrange several items into a single group. For example, if there are numerous Soap products under various brands, all of those brands should fall under the 'Soap' category, just as 'Toothpaste' does. Also, 'Soap' should be seen as a Single Inventory comprised of all soap brands. What kind of adjustments may I make if I so choose? Can someone assist me with their suggestions and solutions? Thanks anyway.