How Do I Upload a File from an HTML Page?

How Do I Upload a File from an HTML Page?

I am struggling with how to upload a file through editing a record from an html page.
I have a page called: Driver Dashboard. On this dash I want the driver to be able to edit one single field on a form called Order_Form. That field is a file upload. 

Here is what I have tried so far that have not worked.
  • Stateless forms. Doesn't work as stateless forms don't support the file attachment field type.
  • Embed Report: I have not been able to embed only the field I need from the form. I can only get it to embed the entire form and it only adding a new record, not updating one.
Any ideas or suggestions? Any help is GREATLY appreciated. Thanks!