How do I get to change the status of a message to seen or delivered

[infinite-dev22]

How do I get to change the status of a message to seen or delivered and also how do I set the unread banner and How do I get the scroll to first unread message. I fully understand that this 👇️ is how a message status is updated

final updatedMessage = p0.copyWith(status: Status.delivered || Status.seen);
FirebaseChatCore.instance.updateMessage(updatedMessage, widget.room.id);
setState(() {});

Where do I add the above so that a message's status is updated accordingly.

I also understand that to scroll to first unread message I use this 👇️

const ScrollToUnreadOptions(
  lastReadMessageId: 'lastReadMessageId',
  scrollOnOpen: true,
)

What do I place at lastReadMessageId, i get it's the message id but how do i get this.