[Exim] Mail forwarding

I am new to the Linux world and to Exim

My office has a in-house web server on which Exim v2.11 is running

My 2 questions are:-

(a) How do I upgrade to v3.20

(b) Is there a way to remotely access incoming mail by keying in an URL with
a port number
instead of configuring OUTLOOK. This is required since AOL does not allow
using OUTLOOK

(b) Besides retaining incoming messages, I need to forward mail to an
account with AOL.
How do I configure so that incoming mail is retained on the server and a
copy is sent out
to an account with AOL

Awaiting your suggestions

Thank you