How to activate and diactivate DND from calling from a DID


I am new here,

I need an information how can i do this:

Extentions: 101,102,103,104 etc (all the calls are diverted to their mobiles so users are always offline)

DID NUMBER: 0123456

I want that when the user 101 calls the DID 0123456 the system asks which Extention do you have? the user digit 101 and then the system asks if he want to deactivate or activate the DND.

Please let me know how can i do this.
Thank you.

Of course the audio file i will create them.