Create media (attachment) post type not working

I see that one of the post type options is ‘media’ (attachment) and I’ve tried it out without any luck.

I added a file upload field assuming it would be automatically detected and used as the attachment file, but the attachment post is created without a file, empty.

Secondly, I tried attaching the file uploaded to the ‘media’ post created. I know this is bad way to do things, attachment on attachment. But I get 2 separate files, really messy.

Please help me. I want to simply upload to the media library, being able to modify its title and excerpt with your plugin. This feature is essential to my website.

Thank you for the plugin ??