So I have three categories of items. First is soaps (5 types of soaps), second is necklaces (5 types of necklaces) and the third is T-shirts (10 types of T-shirts). I want to offer a package where the buyer can choose one of the 5 soaps, one of the 5 necklaces and one of the 10 T-shirts for $30. I don't want to sell the items individually. The items must be purchased as part of the package. Can I set this up in Shopify? How?
Check out bundle apps on the Shopify app store. A lot of them create custom pages within your theme so the user can then select between the different options and add them all to checkout.