How do I use Push, or what exactly is it.

First question, what's your e-mail? As far as I know, these are the 3 ways to get push e-mail to the iPhone:

1) With a .Me account from Apple.
2) From a Microsoft Exchange server.
3) From Yahoo's premium paid e-mail.

Do you have any of these? If not, it won't affect you.

But just so you know what "push" is, it's when a new e-mail is sent TO your phone right when it's sent. Other e-mails will pile up in your in box, and the iPhone will check every 15, 30, or 60 minutes (depending on your settings) and download (or PULL in) every new message it sees.

Push e-mail is more like a text message or phone call...it gets sent one at a time right when it's originally sent.