Now, this is a topic that tends to overwhelm many beginning software developers because it can feel like there is so much to know, and it can be difficult to even know where to start.
I can just about guarantee that, even if you are a beginner, if you can write good, clean, concise, and understandable code that expresses its meaning in the structure itself, just about any interviewer who sees your code is going to assume you are an experienced professional.
And to some degree you will be, or at least on the path to be, because you’ll be treating this career as a profession, not just a job: a sign of a true craftsman.
I’m a big supporter of helping software developers develop “soft skills” in addition to their technical skills—in fact, I wrote a complete book about it—but there is no denying: technical skills are important.
I mean, if you can’t actually write code and develop software, all the soft skills you learn won’t really do you much good.
For example, there are several algorithms that are commonly used for sorting lists of things programmatically.
Each of these sorting algorithms has a different set of properties regarding speed, memory size requirements, and the ideal kind of data it works on.
There are plenty of functional programming languages out there today, but the most popular languages and patterns you’ll find in software development are still heavily, if not completely, influenced by object oriented design and analysis.
You should have a good understanding of what a class is, what the different types of inheritance are—and when to use them—as well as understanding terms like polymorphism and encapsulation.
If you want more information on what it means the effectively structure you're code, I recommend this book: “The Clean Coder”.