How do I become more knowledgeable about politics?

I suggest starting with the Library of Congress website. This is a good starting point. From there you can access the Thomas.gov site which is where you can find out everything you could possibly want to know about Congress. You will find the written text of bills, where they are in committee, and who sponsored them. I also suggest doing a search to find out the Representatives in your particular area. You can go directly to their website to find out all the information you want about the individuals. Another fascinating website about campaign funds and who is donating what is available opensecrets.org. Take this one with a grain of salt because it isn't as up to date because they verify their facts and that takes time. You do want to stay away from blogs, magazines, newspapers, etc. Those should be used strictly as a starting point for your own research. They are useful in the extent that the good ones will lead you to their source. Then form your own opinion from there. My biggest piece of advice is to go directly to the source.

Observation and research is how you gain more knowledge. I was about your age when I gained an interest in politics. I learned about the country's ruling laws, the structure of it's government, and certain economic principles governing our economy. From their I observed conversations about politics both online and off. From these conversations I gained some understanding of current events, because they often led me to resources like research, statistics, and news articles. Whenever someone discussed something I found interesting and wanted to know more about, I researched the topic to get a better understanding. The internet is mostly responsible for my political understanding. Eventually if you read enough and observe enough, you'll feel confident in sharing an opinion. Politics, however, is a topic that gets heated and ugly very fast. Chances are you'll run into people who disagree with you more often than those who agree with you. The ones who disagree with you can teach you a good deal as well, so don't let any upset at being disagreed with ever cause you to completely ignore someone else's argument, because it may have merit. The more you know, whether you agree with it or not, the more you can contribute to a political conversation. So in sum: Phase one is research and observation. Phase two is practice, trial, and error. Phase three is more research and observation. It's a cyclical learning method.

I think the first thing you may want to do, is read your country's constitution, or governing documents to understand some of the basics of how the government, and politics work in your country. Then you should look online to learn about your elected leaders. You can also look at the political parties in your country to get an idea of who stands for what. Personally I don't know that much about the politics in your country, so I can't give you a lot of information myself.