As a side, what are some good ways to start understanding the bigger projects? Blogs and documentation are helpful but mostly don't talk about the underlying im

As a side, what are some good ways to start understanding the bigger projects? Blogs and documentation are helpful but mostly don't talk about the underlying implementation details. Digging through the code line by line takes a long time and while one does learn a lot, I am sure there has to be a better way of doing this. Any static analysis tools that help in this regard? Or any other tool/approach that you might recommend?