how to make your react code complicated code example

Example 1: React js tutorial

npx create-react-app my-app
cd my-app
cd src

# If you're using a Mac or Linux:
rm -f *

# Or, if you're on Windows:
del *

# Then, switch back to the project folder
cd ..

Example 2: react quick tutorial

ReactDOM.render(  
    <Hello />,   
    document.getElementById("root")  
);