Hello!
Now I wont to teach you how to install and config React Native for your Windows 7. All process run in Command Prompt.
First. you open Command Prompt
$ pm install -g react-native-cli
$ react-native init AwesomeProject
After your install and create project React native you get the folder project. Now you can follow next step. you run project to android emulator. Now i use Genymotion.
$ cd AwesomeProject
$ react-native run-android
Okey you finish to run project to android emulator. And next you start project.
$ react-native start
And you reload JS on your emulator.
Okey you finish to create first App with React Native 😀