I want to move an object in an elliptical path that goes into the screen and comes out, like our solar system, planet revolving around the sun, but seen from a different angle? How can I do this? please help.
a fairly easy way would be to create the elliptical path on a solid or null and get it the way that you want (double-clicking any point will allow you to stretch a circular path into an ellipse). you could layout several ellipses on the same layer this way, if needed.
once you have the ellipse, you can select its mask path and copy it and paste it into the position property of a layer and the layer will follow that path.
to get different angles (rather than the top-down angle), you'd just make the layer 3d, add a camera and use the camera orbit tool to get different angles. you may also want to enable auto-orient towards the camera (layer>transform>auto-orient).