You want The Movie Database or The TV Database. Not IMDB. Once you renamed your folders and files properly, just rescan your library.
In order to help with identifying a series, Jellyfin can make use of media provider identifiers. This can be specified in your show’s folder name, for example: Series Name (2018) [tmdbid-65567]
or Series Name (2018) [tvdbid-65567]
(imdbid
is not supported for shows)
Source: https://jellyfin.org/docs/general/server/media/shows/
I don’t think it is. Sorry. The benefit of doing this is that if you have to reinstall Jellyfin or move your media library around at a later date, you’ll never have to worry about mis-identification in the future.