candidate selection workflow how can we add values to Details and Description in change step status?

Hello,

In area of candidate submission - >

actions - change step of status 

we would like to add values to the section of "Details and Description"

we navigate to recruiting - administration - candidate selection workflow , but i only see a setup of step or status .

how can we add values to this section please ?

see attached file where we want to add values .

Thanks a lot 

Revital