You're in embedded computing. It's a very different world. Don't judge yourself based on the JavaScript world. It's just not relevant to what you do. And forget

You're in embedded computing. It's a very different world. Don't judge yourself based on the JavaScript world. It's just not relevant to what you do. And forget the degree. Again, not relevant. Now to your question: Write a lot of software. Get code and architecture reviews from people with a lot of experience. Look back over your own code with an eye to editing it. Where can it be tighter? Where could you avoid a class of bugs by putting in a few habits? Read a lot of history of computing, especially off the path that led to your primary tools. It provides a wonderful perspective. And now the weird one: learn applied behavior analysis. It gives you the underpinnings for reasoning about the behavior of humans and animals.