I would highly recommend that you follow this part of the manual
=> A Panda "Hello World" using Python
http://panda3d.org/wiki/index.php/A_Pan ... ing_Python
It clearly explain how to create script file, how to have script load graphic object , etc....
You must be aware that Panda3D is a game engine, it is not a gamestudio.
There is no world editor and stuff like this.
Bold words are keyword to help you decide quickly if this post interest you or not....
(you should be able to understand the post by reading only bold words