docs: add deprecation notice in readme

README.md

@@ -3,7 +3,8 @@
 <p align="center">
   <a href="https://github.com/expo/examples">
     <img alt="create-react-native-app" src="./.gh-assets/banner.svg">
-    <h1 align="center">Create React Native App</h1>
+    <h1 align="center">⚠️ Deprecated</h1>
+    <p align="center">Create React Native App</p>
   </a>
 </p>
 
@@ -29,6 +30,13 @@
 
 </p>
 
+
+# ⚠️ Deprecated
+
+It's recommended to use a framework to build apps with React Native, [learn more](https://reactnative.dev/docs/environment-setup).
+
+---
+
 <!-- Body -->
 
 ```sh