The answers to your questions are highly dependent on which game engine you are using or plan to use. For instance, each game engine handles lighting differently. Some allow you to create the lighting in Maya. Others require that you use their built-in editors to add lighting.

Scale is also something dictated by the engine. Maya's default unit scale is 1 unit = 1 centimeter. Some game engines respect that value. Others are more arbitrary.

As for the camera issue, you'll want to adjust the near and far clipping values. Also, you can just rotate the camera around. To make manipulating the camera easier, set one of your viewpanels to be the camera, then navigate it into place like the perspective view.