I'm a self-taught developer and I've had to improve my coding skills over the last 5 years with the patience of close dev friends & coworkers. I'll be completely honest and tell you I didn't really understand the underlying way the Java language worked until my first professional job as a junior Android developer. One colleague was very patient with me as I asked likely the most basic coding questions. So don't think you need to know everything to make new things and have an impact.
I decided to open-source my published Android app AdNotes since I've never contributed anything to the open-source community. It doesn't include all the latest & greatest Android features and APIs but it's one of the apps that's helped me learn Kotlin and other small things over time. I hope it helps at least one dev out there and that this is the first of many things I can contribute to the open-source community.
GitHub Repo for AdNotes
Thanks for reading!