How do I sinc hp Windows with iPhone 12 and iPad so that if I delete an email on one, the others reflect that action?

Mail does not sync between devices. Instead all devices accessing a mail account sync to the mail server, which has the master copy of all mail. For this to work the mail on all of the devices must be configured as IMAP (or Microsoft Exchange) rather than POP. Then if you delete a message or move it to a folder that change is synced to the mail server, and the next time any other device accesses the server that change is propagated to the device.

If any of your mail accounts are not doing this verify that they are not POP3 accounts in the mail settings on your device.