. Hello, world!

check node version 

node -v

check npm version 

npm -v

 

Now if you want to install application on your system globally run below comand.here -g mean it will install globally  

npm install -g create-react-app

now if you wan to check globally version install in your system you can use below command

create-react-app --version

now if i want to create react app in my folder make a folder and open command prompt inside the folder and install below command

create-react-app new-app

now to start react app

npm start