node.js express and cors install question

Its my understanding I need to install express and cors via the terminal like this
npm install express
npm install cors
but where do I install express and cors specifically?

Below my DIRECTORY STRUCTURE

WEATHER-JOURNAL-APP <------ Do I install express and cors here
    --website <----------------------------- or here???
        ---app.js
        ---index.html
       ---style.css
server.js