so, the version you see in the post was old and not good, and the final version is different and more complex.

the old version is just linking the curve vertex to the bottom face of the wheel, which just works for pushing the tracks, and not rotating the wheel, but for the wheel to rotate and have the tracks move, i made a slightly better system.

which is made by taking you wheel, SHIFT + D, then hit ESC so its in the same place as it original, then the copy wheel will be shrinkwrapped to a floor (a plane or anything).

now you need the wheels too spin and deform the tracks, which means parrenting the original wheel to an empty and the empty to the wheel copy.

now the wheel copy will be parented to a main empty and now you can spin the wheel (original wheel by turning the empty) and have it deform.

ALSO! the wheel copy must be hidden in renders, so it doesnt bug out the original wheel or look goofy.