How do you find projects to work on when learning a new language?

I have been learning C++/Elixir recently and I’ve made a distributed port scanner & and a streaming platform with Elixir (what an amazing language to work with) and some fun in C++ (also super cool to use).

I feel like I gained basic mastery of the languages, but I’ve been meaning to deepen my knowledge of them. However, I don’t know where to start now…

Can you give me ideas, open-source project that I could help, etc… ? Thanks!