midi controller 7 controls VCA

I have a VCA that controls the volume for 3 FX channels.
Is it possible to have a fader on a midi keyboard control the VCA

figured it out but…how can I map 7 controllers to 7 channels in Cubase
all channels need the VOLUME changed by fader on midi keyboard
you can’t map cc7 to all channels…how do I do it.

I have 7 controllers on my keyboard controlling the channel volume of 7 tracks in Cubase, but…
I have to select a track, then that fader effects that tracks channel fader
why can all the faders be active all the time, 1 channel at a time is not real time mixing via midi