React Native iOS and Android folders not present

You can get to that project structure by running:

npm run eject

However, it removes the app from the Expo framework, which adds a lot of nice benefits and abstraction from the Android/iOS code.

One of the points of Expo on top of React Native is that you don't go down to android or ios code. Expo deals with those folders for you, you don't need to interact with them. Is there a reason you need those folders? if so, you will have to eject. Here's the documentation to do so: Ejecting with ExpoKit

i think if you want to develop app with ReactNative you start follow this : Getting Started use React Native.

If you create project with ReactNative just write on your terminal like:

react-native init YourProjectName
cd YourProjectName
react-native run-ios //for iOS

I hope my answer helping you to create project with ReactNative. thanks..