Activate call forwarding to another number

[marine1]

How would one do this on Telkom Mobile?
So if number is off it diverts to another number

Thanks

 

[R13...]

Like this? Imagine the navigation to these settings depend on your phone. I navigated
Phone app > settings >

Picked Telkom as I have dual SIM and from there to divert/forwarding options

 

[marine1]

Thanks will have a look