I know a few engineers at FAANG companies and have the impression the most important thing to them when interviewing candidates is technical mastery of the many subjects in Computer Science. The other thing is to show you can fit within their culture.
One kinda chuckled telling me about an interview where the candidate struggled to estimate how many bits needed to represent the number one million (every engineer should know that 256 is 2^8 since a byte is a fundamental CS unit, so 1000 is about 10 bits , a million is 1000 squared, so the answer is 20 bits). And that was a softball question. They’ll ask you to invert a binary tree or use Dijkstra’s Algorithm on a whiteboard. The ones they love are the ones that write compilers on their own just to see.