E-mail forwarding and distribution groups

E-mail forwarding and distribution groups

I would like to be able to have e-mail forwarding accounts on our domain and distribution groups.

So say if I do person.1@ourcompany.com would forward to person.1@someISP.com without having full account. Can this be done and how?

Second is I need couple of e-mail addresses to be distribution groups. So say I setup careers@ourcompany.com, this e-mail address would distribute received e-mails to users I assign. How can I set this up?