how use function in javascript code example

Example 1: function javascript

var x = myFunction(4, 3);     // Function is called, return value will end up in x

function myFunction(a, b) {
    return a * b;             // Function returns the product of a and b
}

Example 2: how do you create a function js?

//(don't type behind the// type function to after that name it//
function name() {
  (name)=name
  console.log(name)
};
//{ symbol is used o group together code but you must create n index/array of 2(array3)//