JSFiddle - React, Tailwind, and code Playground

HTML

<textarea id="myInput"></textarea> <br>
Counter: <span id="charCount"></span>
<div id="message"><!--put message here--></div>

CSS

textarea { width:300px; height:200px; }

JavaScript

$('#myInput').keyup(function() {
    var len = this.value.length ; 
    $('#charCount').text(len);
    var creditCount = 158;
    if( len > creditCount ){
         var credits = Math.floor(len / creditCount );
         $('#message').html('We will deduct '+  credits  + '  credit from your account;' )
    }
});