Associate “email id” with “post id”

How can I associate the email id with the id of a post?

Let me explain: in my project, for each post (cpt) that I create, an email is sent to a particular user. So, each cpt has a metadata with the status of the mail sent (read, unread, etc…).
I would like that when the user opens the mail, the corresponding cpt metadata is also updated, so that in some way I would have to associate the mail with the post.

Is this possible?
Thank you very much!!