Call forwarding means that incoming calls on a particular number will be redirected to another number of their choice when it is activated on the phone. It is especially useful when dealing with network problems, although it can also be applied for a wide variety of other reasons.
Setting path:
To enable the option, please follow the steps below:
Open the Phone app > Tap More options > Settings > Calling Account > Carrier call Settings> Call Forwarding > Select the Voice call or Video call as per requirement > Select the Appropriate option to forward call > Enter the Mobile number, to which you want to forward calls.
Always Forward: Once enabled all calls would be forwarded
When Busy: Once enabled this feature call will be forwarded once the call is busy
When Unanswered: Once enabled unanswered calls will be forwarded
When Unreachable: Once enabled unreachable call will be forwarded