I would like to know if its possible to archive specific emails based on the /Subject:/ for example if I receive an email with "Website Support" it will archive it in "Support".. is this possible?
You can then use rules like:
Postfix is SMTP daemon. You should do this on MDA or on IMAP server. For MDA you could use sieve scripts (dovecot MDA supports sieve). For IMAP itself, you could use imap-filter (lua). Usually we don't have access to things like procmail/maildrop on remote mail servers. Some webmails' filtering also fancy filter rules as well.