I have found that interactive visualizations are a great way to understand code and systems in general. Now you can have an AI make one in under a minute it's a very useful tool.

https://heyes-jones.com/externalsort/treeofwinners.html

Take this example. I can step through the algorithm, view the data structure and see a narration of each step.

A debugger is useful for debugging edge cases but it is very difficult to learn a complex system by stepping through it.