Add a Custom Post Type Through WooCommerce

Step 1 — hook your price field into WooCommerce

/**
 * Your post type should have a custom field called 'price'. 
 * We just have to make sure that its meta key is '_price'. 
 * How to check that? You can try to inspect the element:  
 * 1) Visit your post type admin page. 
 * 2) Try to add or edit a post in your post type admin page. 
 * 3) Look for the text box that has the price label and right click on the text box. 
 * 4) You should find it's name attribute to be '_price'. 
 * Usually the name is the meta key for a custom field.
 *
 * Add the code below if your meta key is not '_price'
 */
add_filter('woocommerce_get_price','wc_get_price', 20, 2);

function wc_get_price($price, $post) {
  if ($post->post->post_type === 'post') {
    $price = get_post_meta($post->id, 'price', true);
  }
  
  return $price;
}

Step 2 — add the “Add to Cart” button

Heads up: for the “added to cart” confirmation message to actually appear, you’ll need to call `wc_print_notices()` somewhere in your `single-{post_type}.php` template.