Sergey

<script>
  function showDescription(id) {
    $(".description").each(function () {
      $(this).hide();
    });

    $("#" + id).show();
  }
</script>

<ul>
  <li>
    1. <a href="#1" onclick="showDescription('one'); return false;">Один <span>раз</span></a>
  </li>
  <li>
    2. <a href="#1" onclick="showDescription('two'); return false;">Два <span>два</span></a>
  </li>
  <li>
    3. <a href="#1" onclick="showDescription('three'); return false;">Три <span>три</span></a>
  </li>
</ul>

<div class="descriptionContainer">
    <div id="one" class="description">
      <h1>Заголовок 1</h1>
      Lorem Ipsum is simply dummy text
    </div>

    <div id="two" class="description">
      <h1>Заголовок 2</h1>
      Lorem Ipsum is simply dummy text
    </div>

    <div id="three" class="description">
      <h1>Заголовок 3</h1>
      Lorem Ipsum is simply dummy text
    </div>
</div>

<?php
require($_SERVER["DOCUMENT_ROOT"]."/bitrix/modules/main/include/prolog_before.php");
LocalRedirect('https://mysite.ru');