So uh, how do i respond on the cb radio?

[HUNTER1-0]

I picked up the radio and was instructed to press 1,2 or 3 to respond but nothing happened?

[Longjocks]

You have to hold in the mic button. I was using a controller so it was holding RT then hitting Y, X or A. It was part of the prompt.

[Flexo]

You need to hold RMB before that. But answer options available only at certain point of conversation

[M1k3ol]

hold the talk button (right click on mouse or RT on controller), and press the option button (1,2,3 on KB, X, Y, A on controller)