Let’s say I have 2 vector, A and B. How can I find the Vector 3 that is on the path of A and B with Y = 0, or any value for that matter.
You can create a plane with
Plane plane = new Plane(Vector3.up, yCoord);
(yCoord being y coordinate you are looking for)
And then look for an intersection point of the vector with the plane with Plane.Raycast.