How do I use a variable to find a json value?

I am programming a small program that loads a specific localStorage variable. Here’s my code:

function loadInfo(index) {
  var div = document.getElementById('report');
  if (localStorage.getItem("stardata") != null) {
    // read the data saved in localStorage
    var data = localStorage.getItem("stardata");
    // turn the data from JSON into an array.
    var rdata = JSON.parse(data);
    // stringify data
    var afdata = JSON.stringify(rdata);
    var nfdata = rdata[index];
    var adfdata = JSON.stringify(nfdata);
    var aafdata = JSON.parse(adfdata);
    var keys = Object.keys(aafdata);
    var fdata = aafdata[keys];
    div.innerHTML += fdata;
    return;
  }
}

This takes in the data and converts it into strings a few times to get just 1 value. But for some reason, whenever I try to get the value for keys, it does not output anything. I am coding this on a school computer so I can’t access the console. Any help?