Is the fabric of space time 2d or 3d

[6thgrader]

Well when I watch movies I see space time as 2d. But how do we see the space time from Earth to a region lower than earth.

 

[A.T.]

Well when I watch movies I see space time as 2d.

Space-time is 4D. But we cannot visualize this, so we usually just show a 2D slice, with the relevant dimensions.

But how do we see the space time from Earth to a region lower than earth.

There is no "lower than earth" in space. All radial directions (away from the center) are the same. Space-time along the radial line looks locally like shown here:

https://www.youtube.com/watch?v=DdC0QN6f3G4

At a larger scale like this:
http://www.adamtoons.de/physics/gravitation.swf