Google Onsite Interview: what to focus on during preparation?

The interview prep documents for google suggest reviewing things like discrete math, NP-complete problems, various sorting algorithms, and self-balancing trees. I’m curious how heavily I should dive into each of these topics. Personally, I’ve never needed to know which sorting algorithm is used or whether it’s an AVL or red/black BST and I don’t wanna spend a lot of time on that when I could do LC problems or system design on educative. Is a high level overview enough?