How to set metadata for music files?

In windows music files have metadata like artist name, album name associated with them. How is this metadata stored. Is it stored in file system like other file attributes or is it part of MP3 data that Windows Explorer extracts using a MP3 reader plugin?

RSS audio enclosures have length of zero (podcast duration is missing)

I have had success at creating an RSS feed with enclosures containing episodes of my podcast by simply creating a post and inserting an mp3 file from my media library into it via the robust Add Media functionality of the post editor. However, I have found that the RSS feed created from these posts includes an enclosure for each mp3 file with its length attribute set to zero:

Upload media only to DB

I’m using the latest WordPress (5.6) and from what I’ve found out there’s no visible setting for uploading media directly to a DB. Is there such an option somewhere hidden or does WordPress not support DB as a media storage instead of wp-content/uploads?