After adding your SendEmail function and constructing your message and particulars of the notification change your script builder to the Free Flow version as indicated in the top right section of your platform. Under the section Message: you will click enter to create a space and include the following line of code
attachments:file:input.File_upload,file:input.File_upload_2,file:input.File_upload_3,file:input.File_upload_4,file:input.File_upload_5,file:input.File_upload_6
attachments: to indicate you want to attach a file
file: to call the field type file
input.Name_file to indicate which file field you are referring to
You can add as many files as needed but will need to add a "," between each file. Hope it helps let me know if you have any issues.
