Last year I read Masters of Doom by David Kushner after someone mentioned it on Hacker News. It was the best book I had read in a long time. It won't improve your skills, but I think it will motivate and inspire you to immerse yourself (if we're talking programming, doing small projects and getting feedback is a better way to improve your skills anyway).
Paradigms Lost by John Simon. He is often too pedantic, but I find his extreme focus on writing and speaking English properly to be refreshing in a world of laxity. Reading his book definitely improved my writing skills.
I really like “Smell Detectives” by Melanie Kiechle (a little review - https://ivypanda.com/essays/smell-detectives-by-melanie-kiec...). It is a book that focuses on a concerted effort by physicians and public health officials to promote hygiene in the United States’ urban centers. So, pretty informative and interesting if you are a fan of something like this ;)
Deep Work, by Cal Newport : to focus on what matters.
The talent code, by Danie Coyle : to understand the value of deliberate practice.
Brain at work, astonishingly useful mixing practical neuroscience and concrete situations.
Getting things Done : to adopt a good time management system (you can tweak the method).
Good luck !
I never expected a Jocko Wilkins or a Jordan Peterson book here. It's curious how I find more and more psychology aficionados around here and people who enjoy their books without being.
If by skill you mean something you do with your hands (and this includes
coding and math) reading books is not the answer. Repetition by doing,
interspersed with targeted googling, is.
https://www.goodreads.com/book/show/222146.Masters_of_Doom