To get started install Parcel:
npm install parcel
Then point it to your index.html:
./node_modules/.bin/parcel index.html
And go to localhost:1234 in your browser.
For some reason I have notes on doing this:
npm install parcel-bundler --save-dev
npm run dev
And for a final build:
npm run build
You can also tell Parcel to watch a file, which just builds stuff but doesn't start the webserver I think:
./node_modules/.bin/parcel watch index.html