How to get experienced in C++ (at a good pace) enough to build tools, frameworks etc that other programmers, devs. can use?

I have some experience with C++ when I was doing DSA and little bit of CP in college years and recently learning more with learncpp.com and other resources for actual development. I realized at my work that I learnt more python than I did in my college years (going thru tuts & vids) simply because there was a lot of immediate feedback and I was working on real project challenges. I like C++ a lot and that's why I need to know what is the efficient and less time killing process to get good knowledge in it. My "end goal" is not well defined but I would love to create something like a "backend framework" in C++ or tools like Apache Kafka, Spark, Docker, db like Mongo etc. that other programmers would use? Work is busy and I get little time in hand to learn this lang.
Thanks :)

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