I don’t think you’ll find a better return on investment than working through The Elements of Computing Systems (https://www.nand2tetris.org/) which recently got a second edition. It won’t teach you how to make a rendering engine, or even necessarily any data structures or algorithms, but it will give you a big-picture understanding of the practical fundamentals (literally “what is a computer and how does it really work?”) which you can then use to direct your own learning based on what you want to know next.