How is Mike changing the size of proportional editing?

I’m not sure if you can do it as you dont have the keyboard but i imagine corsair has similar software.

This is what i get when i choose a keyboard button. I can choose a mouse function and it has the scroll click on it so i assume it works as if you clicked the scroll wheel and holding it in may do the same effect.

It may differ for you as both my keyboard and mouse are razer but there is a way to do it!