No, I don't think you understand. In cubase, tracks and channels are almost the same. You have these things:
Audio Track - apears as horizontal bar with waveform in the main editing window, AND as a channel with the same name in the mixer window.
Midi Track - same here, except a MIDI channel is added to the mixer and the editing window does not show waveforms but key hights.
VST - when a VST instrument (or DX instrument for that matter) is assigned to a midi track, a VST channel is add to right of the mixer. It does not have a track, and can be used to run VST instruments through plugins, EQ etc.
Group Track - audio tracks can be assigned to this Group Track. In the editing window, now waveforms are shown, only the level of the group track. A group track works similar as an audio track in the way that it shows up as a channel in the mixer, and everything you apply to a group track (level changes, effects etc.) is applied to every audio track that is assigned to that group track.
Busses - don't need to tell you what these do.
So basicly, when you record something on track 1, that instantly goes through channel 1, and then the main bus(ses). When you record on track 2, it goes to channel 2 etc. Now the number of INPUTS that your soundcard kind of depends where something comes in. For instance, my soundcard as only 2 mono inputs. Track (and channel) 1 uses input 1, track 2 uses input 2, track 3 uses input 1, track 4 uses input 2 etc. It just keeps repeating like that. You can set what input should be linked to what track/channel by editing the track properties, and in the upper left corner of the track properties window, you can select which input(s) to use.
Hope that explains it. About the click noise, I have no clue what else it could be. The bleedthrough thing could still be it though, I've heard click sounds get picked up by my own electrical guitar aswell (very softly, but it was there).