Flutter/Firebase messaging App

I have been working on a messaging app using Flutter for almost a year now and I'm getting down to the finer details to wrap this up. I need some help with a few final features that I'm having troubles implementing and need someone with flutter experience to help me finish it.

Edit:
Things left to do:
- messages read/unread/ notifications setup, free to restructure firebase setup
- data storage and removal both on device and in firebase - half done
- security rules properly setup for storage and firestore for user access to media
- deleting files or leaving conversation, how to setup to show for other user still
- fix admob, was working with test unit ID, edit* is working now, get error when screen left open adwidget is already in tree, Ive used uniqueKey() so not sure
- audiowave bubble doesnt load after leaving recording page. need to back out and back into screen to refresh page
- push notifications with alert sound - can tapping on push notification bring to specific chat screen like I do when I get text notifications? already can do test pushes from firebase console, so mostly setup
- requests structure on firebase screen shows both sent and received requests request system already in place
- better email verification setup adjustment, every time it does a check it routes back to homecontroller main screen
- get ready for google play store

The main step I haven't touched because I have no idea how to implement is the first task, the read/unread messages and notifications part. The rest of the steps have either been setup but not working or setup and need some tweaking.

Bidder that is awarded will be contacted again to help with the IOS port over once the app has been beta tested on the google play store.