Welcome to the forum! Please read
this topic to learn how to post code in code or highlight tags and other useful info for new members.
Here are some directions:
Being able to explain elements of programming does not make a programmer. Putting into practice those concepts, knowing which tool to use when and being able to use each tool correctly most of the time so that doing so is as natural as walking, breathing, and sleeping makes a competent programmer. The way to achieve that level of expertise is to practice, practice, practice, and then practice some more.
No one here will tell you that Java is not worth learning or what you should learn. Those are personal decisions you should make based on what you want to do with what you learn.
Good luck!