Which design pattern is suitable for a WordPress plugin?

Question

WordPress

The plugin adds widgets to Elementor, product settings to WooCommerce, uses various hooks from WooCommerce and other plugins. Now I just created a common class and I include files in this class. For example, to change the fields on the checkout page, I created a file in the plugin called Checkout.php and created a class. That is, this is not OOP at all, but ordinary functional code, just in a class. Also, the plugin must connect to another server via the API. How to organize all this correctly? I read about MVC. Does it fit here? What will be the model, view, controller? I realized that viewing is template files with HTML markup, is it possible to connect a file or should it be a method in which a file is connected, which must be called in another class?

class Checkout {
  public function __construct() {
    add_filter( 'woocommerce_checkout_fields', array( $this, 'checkout_fields' ), 10, 1 );
    add_filter( 'woocommerce_checkout_fields', array( $this, 'checkout_remove_fields' ), 10, 1 );
  }

  public function checkout_fields( $fields ) {
    $fields['billing']['billing_first_name']['placeholder'] = esc_html__( 'First Name*', 'textdomain' );
    $fields['billing']['billing_first_name']['label'] = esc_html__( 'First Name', 'textdomain' );
    $fields['billing']['billing_first_name']['priority'] = 5;

    $fields['billing']['billing_last_name']['placeholder'] = esc_html__( 'Last Name*', 'textdomain' );
    $fields['billing']['billing_last_name']['label'] = esc_html__( 'Last Name', 'textdomain' );
    $fields['billing']['billing_last_name']['priority'] = 10;

    $fields['billing']['billing_address_1']['placeholder'] = esc_html__( 'Address (optional)', 'textdomain' );
    $fields['billing']['billing_address_1']['label'] = esc_html__( 'Address', 'textdomain' );
    $fields['billing']['billing_address_1']['required'] = false;
    $fields['billing']['billing_address_1']['priority'] = 15;

    $fields['billing']['billing_email']['placeholder'] = esc_html__( 'Email Address*', 'textdomain' );
    $fields['billing']['billing_email']['label'] = esc_html__( 'Email Address', 'textdomain' );
    $fields['billing']['billing_email']['priority'] = 20;

    $fields['account']['account_password']['label'] = esc_html__( 'Password', 'textdomain' );
    $fields['account']['account_password']['placeholder'] = esc_html__( 'Password*', 'textdomain' );

    return $fields;
  }

  public function checkout_remove_fields( $fields ) {
    unset(
      $fields['billing']['billing_address_2'],
      $fields['billing']['billing_phone'],
      $fields['billing']['billing_company'],
      $fields['billing']['billing_city'],
      $fields['billing']['billing_postcode'],
      $fields['billing']['billing_state'],
      $fields['billing']['billing_country']
    );

    return $fields;
  }
}

Answer 1

The usual refactoring at the level of "readable" and "without duplication" is enough (with smearing into a couple of classes if necessary), MVC and patterns are not the answer to such a question (MVC - because this is a generalized concept and is simply pulled to the web from another topic, but the pattern can appear itself during refactoring, and the boundaries between some of them are conditional).