npm install - Install all plugins and dependencies, this step is mandatory.
npm run dev - Start it in Development mode, be aware this mode is only for developing, it can take a while before starting, also this mode include hot reloading and other cool stuff.
Or for production mode:
npm install - Install all plugins and dependencies, this step is mandatory.
npm run build - This step is mandatory before starting in production mode.
npm start - Start in production mode.