One assumes you have product list table. In your product list, packages are included as products.
Then you need a separate package table that lists/repeats package and product - 2 column minimum. In this table a product is a package (that may not make sense at first but just think of a product as a package of 1 product)
In your sales table they will select from the product list. As part of your order processing that joins to the package table so if they selected a product - it is one product, but if they selected a package - it joins to all records with a matching package ID.
in the end the order is of products - as that is the most granular set - and you include the package identity purely as presentation.