How do i change my email address on my login page?

ok the question probably didnt explain very well. I have my computer set at a 2 minute screensaver. so after my computer is dile for two minutes it'll show a prompt asking me to choose which login member, and then i enter my password. it also says "you have one new email" but i want to change the email address it has now to my email address since i just got this computer. how do i change it? thanks so much for your help!!! xoxox!

How do i change my email address on my login page?
I want jbready38@verizon.net as my sign in e-mail address.