I dont have an answer to your question but as there are here people with a lot of knowledge will like to add another question:

How do I learn not to over-engineer solutions?

This is the feedback that I received on a couple of homeworks from some non-FAANG companies.

What can I read or what to learn to have this skill of doing simple solutions?

What website did you used to find these good B list companies?

They're publicly traded companies. Sort the S&P 500 or NASDAQ and work your way down by market cap. You could go for pre-IPO companies, but that stock should be valued at $0, so it's less competitive with the FANGs (the liquidity event could pan out, or it could never occur, etc).

My current $LARGE_CO is publicly traded with a single-digit billion market cap.