Does anyone know a way that I could list out the products on the form, so that all are visible?
Based on my interpretation, I'm thinking a continuous form in order to display all products. You'd need a quantity field to denote that any particular product record is to be part of an order as you say. Another thought is to either have this form as a subform so that you can have all the order details in the main form (order number, customer, etc.) OR a split form. However, I've never used a split form beyond playing around with a forum problem for somebody so it may be a poor choice for this problem. Have to say I don't care for them much.
Without knowing more about the process, impossible to say definitively what the whole thing would look like. Maybe a temp table(s) (not that the table is temporary, but the records would be) so that you can begin an order and cancel it without having orphaned order records and no order detail records. You do have one table for orders and another for order details, yes?
Not sure how having all products on a form is a great idea - unless there aren't that many. If more than a few dozen, would think you'd want some sort of filter as Orange is suggesting.
The more we hear silence, the more we begin to think about our value in this universe.
Paraphrase of Professor Brian Cox.