For android I would go with either pure java or C/C++ or the mixture of these and not C#. Noone can help you with your confusion. If you given this project then you are probably expected to be able to do it. With google you could probably find the following page yourself:
I think the best place to start is here:
http://developer.android.com/training/basics/firstapp/index.html[
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Advice: If you don't have to use C/C++ libraries then go with pure java application. Java-only programming is much more developer friendly on android.