Media/Album Catalogue Numbering

I am trying to identify my collection with a little more detail. I find that being able to add the individual Media/Album Catalogue number helps locate the actual correct Album/Artist/Cover Art for the particular Track/Album/Artist, I am currently using the comments field/column to store this data, but find that this column is often filled with personal comments and trivia, sometimes it does actually contain this data, but on the whole its generally filled with rubbish. Would it be possible to add this extra column for this identification data?? Please excuse my ignorance as I am not a programmer of any kind so wouldn't have a clue how to do this for myself... Thank you

see the help for a list of supported fields: https://docs.mp3tag.de/mapping

There is a field ITUNESCATALOGID but this is supported only for mp4 files.

You are free to create a user-defined field to store that id.
Either create a custom column in the files list (see https://docs.mp3tag.de/customization/file-list)

or use the extended tags dialogue (Alt-T) and there the "New" button to create a new field.

It depends on where you get this catalogue number. If you get it from the original label who has released this album, you can choose whatever user-defined field you want - as long as your reading software (Mp3tag, VLC etc) can read it.

If you get the catalogue number from online sources like MusicBrainz you could use their id names, like "musicbrainz_albumid" or "musicbrainz_artistid" or "musicbrainz_trackid" (details see MB tags).