If you forward calls to another number on Galaxy S7, depending on the defined condition, either all your incoming calls, when busy, when unanswered or when unreachable, will be forwarded to the destination phone. To add a forwarding phone number on Galaxy S7, so your calls can be forwarded to, do as follows:
1. Open the Phone application on your S7
2. Tap the More button on the top right of the screen and then touch the Settings option
3. Now under the Call Settings, tap to open More Settings.
4. Go to the Call Forwarding settings (On some models and carriers, you need to select the Voice Calls option)
5. Now there are 4 conditions to forward calls: Always forward, Forward when busy, Forward when unanswered, and Forward when unreachable
6. Tap a condition, then type the phone number (or select from contacts), and hit the Turn On button.
7. From now on, if the forwarding condition comes true, your incoming call with be forward to the specified number/contact.
Note that, if your carrier has already specified to forward calls to your Voice Mail number when your phone is unreachable and want to disable it, simply turn that condition OFF.