How to set a default screen Route in react Tab Navigation in React Native

For those facing this issue in 2022, v6.x of React Navigation, the correct way is to specify the initalRouteName prop in the Navigator component. Link to docs

You can add initialRouteName in createBottomTabNavigator I will solve your problem

 const MyApp = createBottomTabNavigator(
      {
        Inbox: {
          screen: Chat,
          navigationOptions: ({ navigation }) => ({
            title: "Inbox"
          })
        },
        Favourite: {
          screen: Favourite,
          navigationOptions: ({ navigation }) => ({
            title: "Favourite"
          })
        },
        Dashboard: {
          screen: Dashboard,
          navigationOptions: ({ navigation }) => ({
            title: "Home"
          })
        }
      },
      {
        initialRouteName: "Dashboard"
      }
    );