SharePoint 2013 List Customize Attach File

On a list, we need to customize the Attach File page 

Can I embed a Div in a iframe - load the file _layouts/15/Attachfile.aspx?

On a list item, add/edit, after click on "Attach File" we need to change the following,

1. Add a Header tile

2. How to we customize "Use this Page to add attachments to an item" to "Use this page to add attachments (supporting documents).   xxx

thanks