How do I use faders for automation?

Keyboard is connected to the PC via firewire.
It’s connected to Cubase as the MIDI input.
I’m not sure I understand the third question. I’ll try to be more clear on what I’m trying to do:

Example: let’s say I have a French Horn vst loaded. I want to play a phrase with my right hand and use my left hand to move faders to also record Modulation and Expression CC automation while I’m playing to create more realistic phrasing.

In the iC settings I see buttons for Read/Write, but I can only get it to record automation for the Volume CC. I tried to figure out a way to use VCA tracks in Cubase, but I’ve never used them before and that might be just for volume - I don’t understand it too well.

Basically, I don’t have the cash for hardware faders right now, and I thought this would be a decent solution since it advertised having a read/write automation feature. I assumed it would be for any automation, but now I worry that iC Pro doesn’t do this at all.

Thanks for your help.