Yes, go to users, then the user from the user list that you want this to apply to.  Click call handling and forwarding.

Activate the ways you want to receive calls.  Example:  Desktop and Mobile App, Desktop Phone, etc.  Place the desktop handset last.  Set the ones you want to ring above the desktop handset and select the "ring for" to 0 seconds.  It seems counterintuitive, but this is how I got it to ring everything simultaneously.

---

Can we add option to set Ring Group for Desktop/mobile app and desk phone (ring simultaneously) then forward the call to a backup number after certain number of rings then forward to Voicemail if not answered. I know ring group and simultaneous ringing are available however I'm looking forward to exclude a number to ring at a later time.

---