Log in your cPanel: yourdomainname.com/cpanel, enter your login and password:

Go to the Email section and click Forwarders:

Select a domain name in the Managing section and click Add Forwarder:

Put an email address that you want to be forwarded in the Address to Forward and Domain fields, select the Forward to Email Address option and put there an email address where you want to forward. Click Add Forwarder:

It’s done!