Q: I have an apple ID with password.  However, I have more then one email address.  I keep getting a message telling me that I have the wrong password for these other ID's. Why can't they all work on the same password?

Because each Apple ID/email has a different password, apparently, because that is how you configured them. Or the other email addresses never were used for Apple IDs.

Your Apple ID

    1. Forgot iCloud Password

    2.  Forgot Apple ID

    3.  Apple ID - Apple Support

    4.  Manage your Apple ID primary, rescue, alternate, and notification email addresses - Apple Support

    5.  If your Apple ID has been locked - Apple Support

    6.  About your Apple ID email addresses - Apple Support

I don't know if the configuration dialog for an Apple ID permits that. I've never tried it myself. I do know you cannot select another email address if it is already connected to an Apple ID. Only one unique email for each Apple ID. Don't know about the passwords, however. My guess is that it won't allow it because of the potential security risk.

You can try changing them here.

Apple ID - Manage