email

I think below flow step configuration should remove people from the campaign flow if they haven't clicked on any of the 3 emails, you can set up something similar in the Remove from List flow step too, if you would like to remove people from a list too. Also, if you would like to use email open as a condition to remove people from campaign instead of the click-email, you can switch the choice step condition from "Clicked Link in Email" to "Opened Email".