There are two parts 1. How things are made: This is your programming language/core concepts/DSA/Problem solving. Don't start with two languages. Start with 1 a

There are two parts 1. How things are made: This is your programming language/core concepts/DSA/Problem solving. Don't start with two languages. Start with 1 along with design/psds/algo. 2. Why things are made: These are the tools like nginx/jenkins/aws/terraform etc. Understand their purpose. Think of how you would have solved the problem (#1), and then go in depth one by one into their detail. If you are not using what you learn regularly, then you will quite easily forget it. So mix 1 and 2 to keep things interesting. As for blogging, start taking private notes first. Eventually you will have a note detailed enough for someone else to read. Then you start to blog.