To let the users associate one or more files with the selected product, it is essential to previously configure specific upload rules for the products of your shop.
Creating upload rules allows the system to know how many uploads to require for the product the user selected and apply a check on the attachment size and width.
To better understand how to create and manage the upload rules, we suggest reading this section of the documentation.
How do I manage the files I receive?
All the files uploaded by the user are attached to the order. Therefore, you need to accede the order detail page to evaluate and then accept or reject the user’s files.