At this point, you should be able to install and use external packages using npm. You probably know about npmjs.com where you can search for packages and read their documentation. You should also be familiar with the package.json file and how to use it to manage your project dependencies.
You don't need to get into the module bundlers and build tools just yet. Just make sure that you are able to use the dependencies installed in the node_modules folder using simple link and script tags in your HTML.
Regarding projects, here are a few ideas that you can try: