Plane L contains 10,000 points in 3D space OXYZ
Plane M contains (normal_vector & center_point). Firstly, finding the perpendicular distance of each point in plane L to the plan M. Example: 10,000 distance corresponding to 10,000 points.
Then check the condition to the Plane M. If the distance < distance_threshold. Example: 1cm or 5mm ====> then, choose those point satisfying that condition only