I don' remember how to use this simple send/auxilia effect/process. Help.

Hello everyone, I have a somewhat embarrassing question, but I can't quite recall how to perform this procedure. I have my Lead Vocal track, and I'd like to send it to a different track, specifically a send or bus track, to add a particular effect, in this case, a simple chorus. What I aim to achieve is not to create an exact copy of the signal, as it happened on the bus track, but "create an auxiliar track, where apply a single plugin to it, and control the intensity of the effect based on the level of the Fader height. So, if the fader is set to 100%, I can hear the chorus effect at full strength,in the opposite, I'll hear the clean voice with no effect applied at all. I can't quite recall what this process is called, but it's typically used to control delay and reverb on vocals. Can someone assist me with this? Base on this picture, I wanna that that chorus effect applied on the bus track CHORUS, sent from MAIN VOCALS track, become less or more intense in relationshipt to the fader height.

Thank you in advance for your time