Having trouble discovering how to set up automatic forwarding from alias

Having trouble discovering how to set up automatic forwarding from alias

Hi, I would like to set up  automatic mail forwarding from one mailbox alias to another email address outside Zoho. Is this posssible? The only options I can find are to forward all emails from the mailbox address, which I definitely do not want to do.
 If it is possible to somehow select only one email alias for forwarding, could you please explain to me how to do that.
If it is not, could this option be added to Zoho Mail please?
Thank you, Prema