To register the custom post types in WordPress, you can write the code manually:

The initial code to add a new custom post type should look like this:

//function.php
// The custom function MUST be hooked to the init action hook
add_action( 'init', 'ahmedcode_custom_post_article' );
// A custom function that calls register_post_type
function ahmedcode_custom_post_article() {
// Set various pieces of text, $labels is used inside the $args array
  $labels = array(
     'name' => _x( 'Custom Articles', 'post type general name' ),
     'singular_name' => _x( 'Custom Article', 'post type singular name' ),
     ...
  );
  // Set various pieces of information about the post type
  $args = array(
    'labels' => $labels,
    'description' => 'My custom post type',
    'public' => true,
    ...
  );
 // Register the post type with all the information contained in the $arguments array
  register_post_type( 'article', $args );
}

Code language: PHP (php)