When you start up Cinema 4D, you will see a blue cube in the toolbar at the top of your document. Clicking and holding the little black arrow brings up other shapes that you can use.
These 4 icons are located on the top right of the program, affecting ONLY the window and not the shape/shapes you are working on.
The Perspective window always pops up every time you open a new document or revisit one, highlighting either one of top, right or front view then clicking on the far right icon on the page takes you inside that particular view. The axis on the bottom left varies too.