JSFiddle - React, Tailwind, and code Playground

JavaScript

var origin = ['a', 'b', 'c', 'd', 'e', 'f', 'g'];
var choosenKeys = [3, 2, 0];
console.log(getChoosenItems(origin, choosenKeys));

function getChoosenItems(origin, choosenKeys) {
  var temp = [];
  for (var i = 0; i < choosenKeys.length; i++) {
    var j=choosenKeys[i];
    temp[j]=origin[j];
  }
    
  var result=[];
  for (var i in temp)
    result.push (temp[i]);

  return result;
}