How to add html to the form?
No need to declare a form element as #type = 'markup', as this is the default type.

$html = '&lt;strong&gt;My HTML&lt;/strong&gt;';

$form['mymarkup'] = array(
  '#markup' =&gt; $html,
);


Refer to: https://api.drupal.org/api/drupal/developer%21topics%21forms_api_reference.html/7.x