Re: "How can I change my email password ...
I got a new iPhone and I can’t get into the emails because it won’t let me in to get a new password ... "
If you haven't already: You may need to add your eMail account to your new iPhone.
How to: Add and remove email accounts on iPhone - Apple Support
Else:
You may want to try going to your eMail provider's website ... (eg: to Yahoo, GMail etc.) where there is often an option on the log-in screen for when you forgot your password. Generally a temporary log-in will then be sent to you, and you can then log in and change your temporary password to one you can remember.
If needed: contact your e-Mail provider for help to change your password.