Pasting the filenames into the title field

I've got about 20-odd thousand directories of FLAC files. Thousands of them have no tag of any kind, just the list of filenames, or Track01. Instead of copying each title and pasting it in the Title field, and going back to delete the track numbers, is there a function I'm missing in the program that will copy these names and paste them in the Title column? I know zero about programming languages. If it can be done by creating a filter, if it can be accomplished by a command that has % in it, I am lost because I don't know what the coding symbols are for or how they work. I've done this manual procedure over 5000 times because I can't find anything in the program that has any effect on the filenames. Help?

Help: in the documentation?

Then MP3tag is not the best program for you.

For a more detailed help, a screenshot of a real filename would be nice.
This should show filenames with track numbers (if there are any) and filenames without (if there are any)

I would just like to be able to copy those filenames and paste them in the next field over.

Try Convert>Filename-Tag
Format string: %track% %title%

This function can be used on all selected files and will work only for those that match the pattern

Thank you so much for helping out! That was exactly what I needed.

Perhaps you could take this one step further if the folder names have the album and/or AlbumArtist details? Add a column to show the path in your screenshot. This could help to add a few more tag fields.