Create local data base

Please someone. How do I create a local freeDB. My efforts have failed so far. Under the options tab, create local index does nothing.

Also can I add my work from CDText or MP3 tagged files I have created.

I have many years of adding CDText to my music CD collection and wish to save in a better location that Nero['s data base.

Many thanks

You would have to download a freedb and its structure e.g. like the source provided by DetlevD
/t/16208/1
(German section).
After you have unpacked the freedb to a suitable location, you have to generate a local index (or use the index files as provided in the link above) so that MP3tag can find entries in the local database.
AFAIK does not edit the database.