You don't need to know everything when you starting out:
One of the things that I remember when I was a Junior Developer. I thought I had to know everything. But in reality, the expectation was how fast can I learn and can I work together with a team.Because when you are starting out, your seniors or supervisor will know that you are no expert and they would be giving you easy tasks that they know you can handle and learn from bit by bit.So don't forget, when you are starting out, focus on sharpening your skills and be a team member.
Learn how to break code apart:
One of the major things in writing code is to learn how can you make it reusable. It sounds easy, but it's a bit tricky in practice.One of the books that I would recommend (I read it as a junior and it helped me to jump-start my career) and is to read clean code written by Robert Cecil Martin.
Last but not least, try to reference the docs:
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