The Official Android Developer page would be a great start. If you don't know Java you'll want to learn it. You can use a canvas to draw your game using the CPU or you can use OpenGL ES 1.x or 2.0. If you don't want to mess with OpenGL then check out frameworks and engines available. I've been using LibGDX which abstracts away the OpenGL and allows you to develop for Windows/Linux/Mac, Android, and the web simultaneously. I've never used it but AndEngine is an Engine if you prefer that over a framework. There is also Unity if you want to use C# and script your games.