AndroidJetpack/voyager/docs/back-press.md

Back press

By default, Voyager will handle back presses but you can override its behavior. Use the onBackPressed to manually handle it: return true to pop the current screen, or false otherwise. To disable, just set to null.

setContent {
    Navigator(
        initialScreen = HomeScreen,
        onBackPressed = { currentScreen ->
            false // won't pop the current screen
            // true will pop, default behavior
        }
        // To disable:
        // onBackPressed = null
    )
}