How to allow users upload several attachments to a form?

If we add an "Upload" feature to a form, do users have the option of uploading more than one attachment?

Is there a maximum file upload size? If so, can we customize the message a user receives, directing them to email any additional files to us?

Hello,

I can suggest to check our guide on How-to-Create-File-Upload-Forms and Changing-the-File-Upload-Size-Limit. 

If you need further assistance, please let us know.