got a lot of EPs and albums but the tag has their correct artist and title but all I want to do is be able to insert the correct track numbers before each track.
I wondered what feature on mp3tag can apply the track numbers to the titles going by the tag.
Why not rename the files from the tag data then?
Convert>Tag-Filename
format string: $num(%track%,2) _ %artist% _ %title%
You can use any character you like for the _ that I used. A character that is not used in ordinary language makes it simpler to retrieve the information from the filename if this should be necessary some time in the future.
It looks like the contents of the field ARTIST to me.
So, you could use the function
Convert>Tag-Tag for field _DIRECTORY
Format string: %artist%
(or as format string %ALBUMARTIST% which ever is better)
This renames the whole folder.
This may merge folders if there are already folders that had that name or get the new name.