JSFiddle - React, Tailwind, and code Playground

HTML

<nav>
  <a href="#" data-showblock="block1">link1</a>
  <a href="#" data-showblock="block2">link2</a>
  <a href="#" data-showblock="block3">link3</a>
</nav>

<div class="blocks">
  <div id="block1">Hello world!</div>
  <div id="block2">Hakuna Matata!</div>
  <div id="block3">Aloha!</div>
</div>

CSS

a {
  display: inline-block;
  border: solid 1px lightgray;
  padding: 5px 10px;
  font-size: 140%;
}
a.active { background-color: orange; }
.blocks div { display: none; padding: 2em; }
.blocks div.active { display: block; }

JavaScript

$('nav').on('click', 'a', function(){
	var id = $(this).data('showblock')
  $(this).addClass('active').siblings().removeClass('active')
  $('#'+id).addClass('active').siblings().removeClass('active')
})