I have noticed alot of cdlc songs that's say the are made for lead, rythm, bass and vocals. How does one use the vocals? In the my path selector it only shoes lead, rythm & bass.

Vocal means the song has lyrics on it,

I guess its called like that in EOF because in other games that use EOF you can use it to actualy play the vocal part but you cant do that on rocksmith,

Here its just for lyrics.

Rocksmith 1 would actually comment on whether you were singing in pitch for the lyrics, but it wouldn't score your singing as far as I ever heard. In Rocksmith 2, the lyrics are just for show, but the Rocksmith team still authors them, presumably in case they ever develop the vocal system more.