To get good at the basics of JavaScript, and from a guy that gets modesty when it comes to writing JavaScript, check out Chris Ferdinandi. He puts together the Vanilla JS Academy, a cohort-based course on learning JavaScript. He also sells some ebooks, and writes excellent daily articles on writing JavaScript. Also, check out his Lean Web presentation and book.
To help you become a better influencer (leader), I recommend the classic book Principle-Centered Leadership by Stephen Covey, at least the first half of the book. You’ll learn to disassociate your choices from your skills, and instead center your decisions on bigger-picture principles.
To help examine and rewrite on-the-spot the underlying assumptions/convictions/mental models at play in your mind, I recommend the book Leadership Agility by Bill Joiner. Another option is to watch some of the videos from my series on Changing Situations Using Mental Reprogramming On Yourself.
To help understand what causes people to buy products (and buy into ideas) – in short, to sell – I recommend Competing Against Luck by Clayton Christensen. It’s a primer on the Jobs-To-Be-Done Theory of buyer behavior.