how to write foreach in a function code example

Example 1: forEach index

const array1 = ['a', 'b', 'c'];

array1.forEach((element, index) => console.log(element, index));

Example 2: javascript foreach call specific value in array

run.addEventListener("click", function () {
    people.forEach((element) => console.log(element.firstname));
  }); // select a specific string in array