What helped me most understanding the tooling around babel & co was to watch an intro video from vue.js on the new Viue 3.0.

Copying anything by hand while he explains it. With minimal package count.

And always use a code generator later like when you start a Typescript/JS project, because you can do so many little things wrong on your own while you don't know enough.

https://classic.yarnpkg.com/en/docs/cli/create/