Also I cannot find how to use collision detection! i am on unity personal in 3d if that helps!
i deleted the cube that lets you move
around and i need it back! help? the
one in the top right corner
Are you referring the Scene Gizmo that is in the upper-right corner of the Scene View?
Unity Manual - Scene View Navigation
Try clicking on the 2D Mode button.
Note that in 2D Mode the Scene Gizmo
is not displayed, because the only
option is to have the view looking
perpendicularly at the XY plane.
Collision Detection
Unity Scripting API - Colilders