Why is it that once i make an email account thereafter i couldn't possibly change the email ID?

Is there any way out? i mean i want to shift all my emails to the new account so that i dont have to forward all the mails page by page....

Why is it that once i make an email account thereafter i couldn't possibly change the email ID?
Chances are good your email provider has some basic filters that will let you do what you need (if I understand correctly). You don't want to have to forward each individual email to the new address. Instead, in options you should see filters or message forwarding or something - you can set it up to forward all messages to the new account if you wish.