Order modification or order id transfer

Can somebody help me please. I want the customer to be able to modify an order after order is made. I want that the client can additional fill in some fields who i created.

If this can not possible, is there a way to add a button to every single order info(on each order), so that when the customer clicks it opens a new page with a form that will have some fields that it can fill in. Here, all I need to transfer from the original order is the order number.

Thanks