I studied in the field of Computer Science for 6 years, bachelor's degree and master's degree. I have studied all the basic programming like C, Java, VB, C#, Python, and etc. When I have free times, I will learn new programming languages and follow new programming trends by myself , such as PHP, HTML5, CSS5, LESS, Bootstrap, Symfony2, and GitHub. So, if someone wants me to write some instructions using these languages, I'm certain that I can do it, not so good but I can get a job done. However, I don't have any favorite programming language. Moreover, I also have studied about algorithms, database, and etc.
Everything I just wrote so far seems that I know a lot in this field. In fact, I feel I am very stupid. I cannot answer 80% of the questions on SO. In spite of those languages??, I have studied. Perhaps it is because I have never worked before.
As there is the Developmental Milestones for children, which refers to how a child becomes able to do more complex things as they get older, I would like to evaluate the same thing but for programming skills. What are the set of functional skills or age-specific tasks that most programmers can do at a certain age range?
In order to evaluate myself, I would like to ask your opinions that all of the skills I mentioned above, are they enough for programmers to know when they are 25 years old?
What are your suggestions in order to improve the skills in this field?