How do I change my Apple ID. It tells me i have to put in a new notification email but i cannot find it

See if anything here helps.

Apple ID email addresses.    

Note the restrictions in the article.

Apple ID Name Change.        

 What to do after you change your Apple ID or password - Apple Support    I suggest doing this before you change your Apple ID or password.

You can find the place to insert a notification email in your Apple ID Account https://appleid.apple.com/#!&page=signin.