How to make a loading animation in Console Application written in JavaScript or NodeJs?

Not really possible in browser console. In Node.js:

var twirlTimer = (function() {
  var P = ["\\", "|", "/", "-"];
  var x = 0;
  return setInterval(function() {
    process.stdout.write("\r" + P[x++]);
    x &= 3;
  }, 250);
})();

You can do it in the browser console as well:

var loading = (function() {
  var h = ['|', '/', '-', '\\'];
  var i = 0;

  return setInterval(() => {
    i = (i > 3) ? 0 : i;
    console.clear();
    console.log(h[i]);
    i++;
  }, 300);
})();

// clearInterval(loading) to stop it.

The setInterval() method calls a function or evaluates an expression at specified intervals (in milliseconds) at each 250 ms the value in the p array is printed on the console. The setTimeout() method calls a function or evaluates an expression after a specified number of milliseconds. setInterval is used as a loop here. Using the clearInterval, the loop is breaked after 5000 ms using setTimeout.

const P = ['\\', '|', '/', '-'];
let x = 0;
const loader = setInterval(() => {
  process.stdout.write(`\r${P[x++]}`);
  x %= P.length;
}, 250);

setTimeout(() => {
  clearInterval(loader);
}, 5000);