JSFiddle - React, Tailwind, and code Playground

HTML

<textarea name="txtScript" id="word_count" cols="30" rows="10"></textarea>
<br>
Total word count: <span id="display_count">0</span> words. Words left: <span id="word_left">200</span>

JavaScript

$(document).ready(function() {
  $("#word_count").on('keyup', function() {
    var words = 0;

    if ((this.value.match(/\S+/g)) != null) {
      words = this.value.match(/\S+/g).length;
    }

    if (words > 200) {
      // Split the string on first 200 words and rejoin on spaces
      var trimmed = $(this).val().split(/\s+/, 200).join(" ");
      // Add a space at the end to make sure more typing creates new words
      $(this).val(trimmed + " ");
    }
    else {
      $('#display_count').text(words);
      $('#word_left').text(200-words);
    }
  });
});