first of all install nodejs form nodejs.org 

open your command prompt and type :-


npx @react-native-community/cli init MyFirstApp:-

open project folder and open your App.tsx file :-

App.tsx file code :-

import 'react-native-gesture-handler';
import React from 'react';
import { NavigationContainer } from '@react-navigation/native';
import { createNativeStackNavigator } from '@react-navigation/native-stack';

import HomeScreen from './screens/HomeScreen';
import DetailsScreen from './screens/DetailsScreen';
import ProfileScreen from './screens/ProfileScreen';
import SettingsScreen from './screens/SettingsScreen';

const Stack = createNativeStackNavigator();

const App = () => {
  return (
    <NavigationContainer>
      <Stack.Navigator initialRouteName="Home">
        <Stack.Screen name="Home" component={HomeScreen} />
        <Stack.Screen name="Details" component={DetailsScreen} />
        <Stack.Screen name="Profile" component={ProfileScreen} />
        <Stack.Screen name="Settings" component={SettingsScreen} />
      </Stack.Navigator>
    </NavigationContainer>
  );
};

export default App;


MyFirstApp/screens/HomeScreen.tsx file   code:-

import React from 'react';
import {
  View,
  Text,
  TouchableOpacity,
  StyleSheet,
  StatusBar,
  ScrollView,
} from 'react-native';

const HomeScreen = ({ navigation }: any) => {
  return (
    <ScrollView contentContainerStyle={styles.container}>
      <StatusBar barStyle="light-content" backgroundColor="#1e1e1e" />
      <Text style={styles.header}>Welcome to My App</Text>

      <TouchableOpacity
        style={styles.button}
        onPress={() => navigation.navigate('Details', { message: 'Hello from Home!' })}
      >
        <Text style={styles.buttonText}>Go to Details</Text>
      </TouchableOpacity>

      <TouchableOpacity
        style={styles.button}
        onPress={() => navigation.navigate('Profile')}
      >
        <Text style={styles.buttonText}>Go to Profile</Text>
      </TouchableOpacity>

      <TouchableOpacity
        style={styles.button}
        onPress={() => navigation.navigate('Settings')}
      >
        <Text style={styles.buttonText}>Go to Settings</Text>
      </TouchableOpacity>
    </ScrollView>
  );
};

export default HomeScreen;

const styles = StyleSheet.create({
  container: {
    flexGrow: 1,
    backgroundColor: '#121212',
    padding: 24,
    alignItems: 'center',
    justifyContent: 'center',
  },
  header: {
    fontSize: 28,
    color: '#fff',
    marginBottom: 32,
    fontWeight: 'bold',
  },
  button: {
    backgroundColor: '#4a90e2',
    paddingVertical: 14,
    paddingHorizontal: 28,
    borderRadius: 12,
    marginVertical: 12,
    width: '100%',
    alignItems: 'center',
    elevation: 4, // Android shadow
    shadowColor: '#000', // iOS shadow
    shadowOffset: { width: 0, height: 2 },
    shadowOpacity: 0.3,
    shadowRadius: 4,
  },
  buttonText: {
    color: '#fff',
    fontSize: 18,
    fontWeight: '600',
  },
});




MyFirstApp/screens/DetailsScreen.tsx file code:-

import React from 'react';
import { View, Text, Button, StyleSheet } from 'react-native';

const DetailsScreen = ({ route, navigation }: any) => {
  const { message } = route.params || {};

  return (
    <View style={styles.container}>
      <Text style={styles.title}>Details Screen</Text>
      <Text>{message}</Text>
      <Button title="Go to Home" onPress={() => navigation.navigate('Home')} />
    </View>
  );
};

export default DetailsScreen;

const styles = StyleSheet.create({
  container: { flex: 1, justifyContent: 'center', alignItems: 'center' },
  title: { fontSize: 24, marginBottom: 20 },
});



MyFirstApp/screens/ProfileScreen.tsx file code:-


import React from 'react';
import { View, Text, Button, StyleSheet } from 'react-native';

const ProfileScreen = ({ navigation }: any) => {
  return (
    <View style={styles.container}>
      <Text style={styles.title}>Profile Screen</Text>
      <Button title="Go to Home" onPress={() => navigation.navigate('Home')} />
    </View>
  );
};

export default ProfileScreen;

const styles = StyleSheet.create({
  container: { flex: 1, justifyContent: 'center', alignItems: 'center' },
  title: { fontSize: 24, marginBottom: 20 },
});



MyFirstApp/screens/




SettingsScreen.tsx file code:-

import React from 'react';
import { View, Text, Button, StyleSheet } from 'react-native';

const SettingsScreen = ({ navigation }: any) => {
  return (
    <View style={styles.container}>
      <Text style={styles.title}>Settings Screen</Text>
      <Button title="Go to Home" onPress={() => navigation.navigate('Home')} />
    </View>
  );
};

export default SettingsScreen;

const styles = StyleSheet.create({
  container: { flex: 1, justifyContent: 'center', alignItems: 'center' },
  title: { fontSize: 24, marginBottom: 20 },
});



finally run it:-

npx react-native run-android