CTRL + [Something] = Input. How do i do?

So I have a basic camera zoom blueprint for the top down character that I saw someone suggest using and they said to go to the project settings to set the bindings. Pic -

now I’m just wondering if its possible to instead of having just mouse wheel down/up I could set it to CTRL + Mouse wheel down/up. Would also be very useful if someone could explain to me how to set a max or cap on how far out the player can zoom and how far in the player can zoom as to alleviate potential clipping issues. ^-^

said blueprint-

You can add Left Ctrl to your Action Mappings in Project Settings, Input, and store a boolean variable from Input Event. Then, when you scroll your mouse you can check if Ctrl input was enabled.
If you want to constraint camera zoom you can use Clamp node just before you set Target Arm Length.