my idea is to create a document tree, with posts, inserting a file field, for download, but I can’t replace the documents already inserted. I can only delete them and insert the new file, without changing an entry already made (using the pencil icon). I hope I explained myself.
The pen button opens the standard WP edit screen for the file. This works the same as if you went to the media folder and opened the WP editor for it from there. You can’t delete the button, but you can probably hide it with some custom CSS added to the admin of your site.