Keep a “decision“ journal. Write down your reasons for your choices. Make predictions and observe the results. Revisit weekly.

I did this and it helped me enormously. Not only understanding actions/outcomes of myself and others but also flaws I had in tons of my own mental models and behaviors.

I would also recommend listening to the „You are not so smart“ and „beat your genes“ podcasts. Both will reference papers and books that provide further reading materials.

As far as books go, I got a lot from Nassim Talebs work and the great mental models series.

No particular book, but 2 hi quality areas that may boost your reasoning and critical thinking skills: philosophy in general (like ancient greek philosophers etc) and theology (from medieval arguments about how many angels on the tip of the needle to modern debates).

Historically those were the 2 main intellectual and spiritual drivers behind the creation and rise of modern reason based (as opposed to superstition magical thinking) western society and modern science, etc.

I found Rational Choice in an Uncertain World: The Psychology of Judgment and Decision Making, by Hastie & Dawes, useful.

Critique of Pure Reason and Philosophical Investigations -- I studied philosophy as an undergrad and only helpful modulo your definition of "helpful" of course. For me, expecting my best decisions to be at least partly wrong and my knowledge to always be incomplete.

How to Decide: Simple Tools for Making Better Choices by Annie Duke

Here you go, Ethics by Benedict de Spinoza. https://www.gutenberg.org/ebooks/3800 <-- Free & legal download.

Critical thinking or engineering ethics courses. Look up the required books and buy one of those.

Writing a few papers and critique reading a few on the subjects were helpful.

Thinking fast and slow by Daniel Kahneman will help you understand why many of the technical decisions you are making are going wrong.

A Practical Guide To Critical Thinking by David A. Hunter

Can you please share a few example? Many technical decisions rely on experiences.

I'm gonna be that guy and say LessWrong.

Yeah, yeah. Say what you will. An addictive forum of people thinking really hard about all kinds of weird topics probably did more for me than any single book I read.