Does it make sense to build your model far away from the axis lines?

So I try to make my second model but not sure why I would start a model close to or even over the axis lines, it might confuse me or looks to busy.
Or am I missing something

Another thing when I try to make my first thing in my new model, I tried a rectangle but the further away I want to draw it then it becomes green and it stands instead of blue and laying, why is this and how can I get around this?
I want to make a blue rectangle far away from axis lines but it becomes green…

It is generally not a good idea to model very far away from the global axis. In extreme cases it can cause visual problems and cause the model to behave strangely. You can turn the axis off in View>Axis. The green, red, and blue are the axis colors for x,y,z dimensions and and when applied to rectangle you are creating they tell you which plane you are creating in. This is largely determined by which way you are looking, or by surrounding objects, the inference engine trys to draw the rectangle flat against the direction you’re looking. So if you are looking down, you will get a blue rectangle. You can also lock the axis direction using the arrow keys to force a rectangle to be drawn on any plane you want. Up arrow is blue axis, right is red and left is green.

I recommend creating the model’s entities near (or right at) the world origin - where the red, green, blue axes intersect. The axes give a frame of reference, which may help while creating the model, orbiting and panning around, etc. The axes can be temporarily hidden from view if they become distracting - see the functions on the View menu.

On a practical level, the total dimensional extent of the model - the overall distance spanned by the model’s geometry plus the world origin - affects how smoothly or completely SketchUp renders the model in the viewport. At very large extents, SketchUp will begin visually clipping the model - hiding foreground portions as you zoom in. For example, if the model is displaced many miles (kilometers) from the origin, display artifacts can begin to appear.