JSFiddle - React, Tailwind, and code Playground

HTML

<span style="font-size:20px;">Your bid:</span> 
<input type="number" name="bid" class="form-control" style="max-width:250px; margin-top:10px;">
<br>
<input type="button" onclick="cal()">
<span style="font-size:20px;" >Our Fee (10%):</span>
<input type="number" name="fee" readonly class="form-control" style="max-width:250px; margin-top:10px;">
<br>
<span style="font-size:20px;">You'll paid:</span>
<input type="number"  name="get" readonly class="form-control" style="max-width:250px; margin-top:10px;">

JavaScript

function cal(){
  var bid = Number(document.getElementsByName("bid")[0].value);
  var result1 = bid * 0.1;
  var result2 = bid - result1;
  document.getElementsByName("fee")[0].value = result1;
  document.getElementsByName("get")[0].value = result2;
}