[ruph123]

How to tackle it?

To me there are either two ways: when you are trying to learn the thing XYZ you are seeking, drill down to the first thing you don’t understand and consult a lower level resource. Continue until you reach a level you understand. And the second way is: Re-learning “all” of essential math and then going back to XYZ.

I don’t think the second step is feasible, as you cannot possibly learn everything in a breadth-first kind of way until you are deep enough to learn the (now level-adjacent) topic XYZ.

But for strategy 1, the question is 1) how to identify the problem that you are lacking (e.g. how to isolate math gibberish into a concrete concept) and 2) how to find a good resource to learn and practice this concept at this level?

I do struggle with this and sometimes randomly learn some lower concept again but notice later it did not help me in the end and just left me with a million untied knots that were infeasible for me to entangle.