$(function() {
    $(".quiz:first input:first").focus();
    $(".quiz input").keypress(function(e) {
        var keyCode = e.keyCode || e.which;
        if (keyCode == 9) {
            e.preventDefault();

            if ($(this).parents(".quiz").next().find("input:first").length > 0) {
                $(this).parents(".quiz").next().find("input:first").focus();

                /*
              //OR Another way to find next input selector is:
              $(this).closest(".quiz").next().find("input:first").focus(); 
              */

            } else if ($(this).parents(".quiz").prev().find("input:first").length > 0) {
                $(this).parents(".quiz").siblings(".quiz:first").find("input:first").focus();

                /*
              //OR Another way to find next input selector is:
              $(this).closest(".quiz").siblings(".quiz:first").find("input:first").focus(); 
              */
            }
        }

    });
});

Setting Validate Copy Format

.header{
  border-bottom:1px solid #445599;
  display:block;
  background:#447797;
  padding:0px;
  
}
.quiz{
  background:#bbaadd;
  border:1px solid #445599;
  padding:2px;
  display:inline-block;
}
.quiz input{
  border:1px solid #113388;
}
.quiz input:focus{
  background:#d98866;
}

Setting Validate Copy Format

<div id="panel">
  <div class="quiz">
    <span class="header">
      Div-1
    </span>
  	<p>
      Question-1? 
      <input type="text" tabIndex="1" />
    </p>
    <p>
      Question-2? 
      <input type="text" tabIndex="2" />
    </p>
    <p>
      Question-3? 
      <input type="text" tabIndex="3" />
    </p>
  </div>
  <div class="quiz">
    <span class="header">
      Div-2
    </span>
  	<p>
      Question-4? 
      <input type="text" tabIndex="4" />
    </p>
    <p>
      Question-5? 
      <input type="text" tabIndex="5" />
    </p>
    <p>
      Question-6? 
      <input type="text" tabIndex="6" />
    </p>
  </div>
 </div>

Copy Format

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