My advice for CS or mathy people in 2023 would be:
1. CS/Programming - Learn more about programming languages and how they work. Learning it creates mental models which can help you pick up new languages faster and use them more judiciously. Check out Dan Grossman's 3 part Programming Langauages course on Coursera. Or maybe learn some PL Theory. There are many books. Pick what suits you.
2. Math - Learn how to solve Fermi problems or approximation problems. It is also known as Street Fighting Mathematics. It helps develop intuition as to what the answer to a problem can be and provides you with a vague foggy path nonetheless a path to start progressing forward.
There is a course on MIT OCW by Prof Sanjoy Mahajan called Street Fighting Mathematics: https://ocw.mit.edu/courses/18-098-street-fighting-mathemati....
It uses a book of the same name. You can find more about it here: http://streetfightingmath.com/index.html
There is also Concrete Mathematics by Don Knuth et al. You can find it for free as a pdf if you google properly. It is a mixture of discrete and continuous math.
Also Polya's How to Solve It.