Intersection to the ground from point A to point B

I’d like to find the intersection to the globe in a scenario like this where there are the two points intersect with the ground as shown on the image, could someone guide me onto what I’d need to use, knowing that I can use CLAMP_TO_GROUND to clam the point once I find it however I am unable to find the point itself.

You can use the scene pickPosition or camera pickEllipsoid function to find intersections with the globe. Here is an example that uses pickEllipsoid to display latitude and longitude of the mouse on hover: Cesium Sandcastle.