You need to undesrtand how to calculate the volume and the surface of a cone. See the image below to get a better understanding;

Here is the code with the solution:

function cone(input) {
let [r,h]=input.map(Number);
let s = Math.sqrt(r * r + h * h);
let volume = Math.PI * r * r * h / 3;
console.log("volume = " + volume);
let area = Math.PI * r * (r + s);
console.log("area = " + area);
}
cone(["3.3", "7.8"]);