You'll need to give more details. What program are you using to access your email?
If you are using a web based email service (Gmail, Yahoo! Mail, Hotmail, etc.) then you don't need to do anything except point your internet browser to the email website.
If you are using outlook, thunderbird, etc. (an actual program on your computer) then there is some setup involved to pull in your email account.
Regardless, your email address is not locked to the computer you are using.
Post back more detail please.