Add a custom form only to a particular content type
If I'm not wrong, I think you are trying to display your custom form in the node view of a particular content type. You can do this in two ways.

The first approach is to implement hook_node_view() from the module level.

function MYMODULE_node_view($node, $view_mode = 'full', $langcode = NULL) {
    if($view_mode == 'full'){
        if($node-&gt;type == 'your_content_type'){                 
            $node-&gt;content['my_form'] = array(     
                '#markup' =&gt; drupal_get_form('your_form_id'), 
                '#weight' =&gt; 1,
            );
        }
    }   
}


The second approach is to implement hook_preprocess_node() from the theme level.

function MYTHEME_preprocess_node(&amp;$variables) {
  if ($variables['view_mode'] == 'full' &amp;&amp; node_is_page($variables['node'])) {
    if($variables['node']-&gt;type == 'your_content_type'){
        $variables['content']['my_form'] = drupal_get_form('your_form_id');
    }   
  }
}