When I read an email on my iPad I am not receiving it on my laptop - how do I sync them?
In order to have your email sync on multiple devices, make sure your account is set up to use the IMAP protocol. Most free services, like Yahoo!, are set to use POP by default, which does not sync.

Go to your Yahoo! account settings at yahoo.com and change it to use the protocol to IMAP. You will have to then delete/change the email account on your iPad, and set it up as IMAP as well.