Add navigation functionality to 5 buttons on geckoview based web browser (Kotlin)

APK app with geckoview engine / simple browser has 5 navigation button user interface (see attached picture). I need to add glue code and make these 5 buttons functional with geckoview browser sessions.

Forward button – go to next page
Home button – go to home page (ex. Google.com)
Hamburger button – show all geckoview sessions / similar to showing all open tabs
Reload button – re-load current url / page
Back button – go to previous page

The apk / source code for this app will be provided, upon being selected for this project. Please let me know, if there are any questions.