fieldset

<!DOCTYPE html>
<html>
<head>
  <meta charset="UTF-8"/>
  <title>test</title>
</head>
<body>
<form>
 <fieldset>
  Name: <input type="text"><br>
  Email: <input type="text"><br>
  Date of birth: <input type="text">
 </fieldset>
</form>
</body>
</html>

legend

<!DOCTYPE html>
<html>
<head>
  <meta charset="UTF-8"/>
  <title>test</title>
</head>
<body>
<form>
 <fieldset>
 	<legend>Personalia:</legend>
  Name: <input type="text"><br>
  Email: <input type="text"><br>
  Date of birth: <input type="text">
 </fieldset>
</form>
</body>
</html>

fieldset - disabled

<!DOCTYPE html>
<html>
<head>
  <meta charset="UTF-8"/>
  <title>test</title>
</head>
<body>
<form>
 <fieldset disabled>
 	<legend>Personalia:</legend>
  Name: <input type="text"><br>
  Email: <input type="text"><br>
  Date of birth: <input type="text">
 </fieldset>
</form>
</body>
</html>