Hey there!
Philosophy! What an awesome subject! I am currently studying Philosophy 1/2 and I have to say it was the best choice I made regarding subject for year 11. I find philosophy quite strenuous at times because it really requires you to think about things. In saying that it isn't a really hard subject, but just like any other subject, it requires effort in order to do well. I study it by distance though, so it may be a bit easier as a classroom based subject as philosophy is really discussion based, and sharing ideas is pivotal in doing philosophy. You do need to have a genuine interest in actually doing philosophy in order to get something out of it. Otherwise you will be sitting in class, wasting your time, wondering what the point is of studying what we study in philosophy and probably find it atrociously boring. I can't count the number of times I have sat there, wondering about the world, and life, and what everything means. If that sounds like you, then I think you would love philosophy.
What we learn? Basically it is split into two units at year 11 level (assuming that is what you are referring to):
Unit 1 involves the study of Metaphysics (The branch of philosophy that deals with the first principles of things, including abstract concepts such as being, knowing, identity, time, and space.) And Epistemology (The study of knowledge, especially with regard to its methods, validity, and scope, and the distinction between justified belief and opinion.) With a few activities based around logic and reasoning thrown in for good measure.
Unit 2 involves a study based around Ethics and Morality (basically what's right and wrong, good or bad, the existence of god and the philosophy of religion etc.)
I would highly recommend philosophy to anyone, as it is really interesting and is a great foundation for a career in Law, Politics, and areas like that.It really helps develop your writing and reading skills and I find it compliments subjects like English, Literature, History, Religion & Society, Politics and even aspects of Legal Studies and Business Management.
I hope that answers your questions, and was of some sort of help. If you have anymore questions, feel free to reply and I'll do my best to answer them!