Other contributors have said "What is the job of cone?" is the same question as "What is a cone?". If you believe that these are not asking the same thing and should be answered differently, click here.
If you picked a point that is on a line perpendicular to the plane and that goes through the center of the circle, then you have set the conditions to make a right circular cone. This 3-dimentional geometric figure is fun to investigate. Use the link below to lean more about the cone.