Can I specifically command sidecar to use only USB not airplay for connecting to iPad

Dear Apple developers,

I am trying to use Sidecar with only USB, not airplay (because airplay slowdown my wifi quite a lot). However, I always found frustrated as when I turned on Sidecar even with USB-C connected, the system directly recognize iPad using airplay not USB-C. Sometimes I need to replug the USB-C cable for a couple of times and wait until it finally recognizes USB-C rather than airplay.

Also I noticed that there is no sidecar button on the menu bar of my macbook pro (Big Sur). Is there a default for Big Sur? What if I want to have it on the menu bar so that I don't need to repetitively go to system reference to activate sidecar?

Many thanks!

Minghao