[NSFW] Custom Wocommerce Payment Gateway Help

<?php
/*
Plugin Name: Liberty Dollar Financial Association (Payment Gateway)
Plugin URI: http://www.ldfa.nl/
Description: Add a LDFA Buy Now Button to your website and start selling with Liberty Dollar Financial Association today. No Coding Required. Official Liberty Dollar Financial Association Partner.
Version: 0.0.1
*/

if ( ! in_array( 'woocommerce/woocommerce.php', apply_filters( 'active_plugins', get_option( 'active_plugins' ) ) ) ) return;

add_filter( 'woocommerce_payment_gateways', 'ldfa_add_gateway_class' );

function ldfa_add_gateway_class( $gateways ) {
    $gateways[] = 'WC_LDFA_Gateway'; // your class name is here
    return $gateways;
}

add_action( 'plugins_loaded', 'ldfa_init_gateway_class' );

function ldfa_init_gateway_class() {
    class WC_LDFA_Gateway extends WC_Payment_Gateway {
        public $app_id;
        public $cart_id;
        public $publishable_key;
        public $merchant_key;
        public function __construct() {

            $this->id = 'ldfa_payment';
            $this->icon = ''; 
            $this->has_fields = false; 
            $this->method_title = __('LDFA Payment Gateway', 'woocommerce');
            $this->method_description = 'Take Payments Via Liberty Dollar Financial Association Wallet.'; 
            $this->supports = array(
                'products'
            );
            $this->init_form_fields();
            $this->init_settings();
            $this->title = $this->get_option( 'title' );
            $this->description = $this->get_option( 'description' );
            $this->enabled = $this->get_option( 'enabled' );
            $this->app_id = '';
            $this->cart_id = '';
            $this->publishable_key = '';
            $this->merchant_key = '';
            add_action( 'woocommerce_update_options_payment_gateways_' . $this->id, array( $this, 'process_admin_options' ) );
            add_action( 'wp_enqueue_scripts', array( $this, 'payment_scripts' ) );

        }

        public function init_form_fields(){

            $this->form_fields = array(
                'enabled' => array(
                    'title'       => __('Enable/Disable', 'woocommerce'),
                    'label'       => 'Enable LDFA Gateway',
                    'type'        => 'checkbox',
                    'description' => '',
                    'default'     => 'no'
                ),
                'title' => array(
                    'title'       => __('Title', 'woocommerce'),
                    'type'        => 'text',
                    'description' => __('This controls the title which the user sees during checkout.', 'woocommerce'),
                    'default'     => 'LDFA Payment Gateway',
                    'desc_tip'    => true,
                ),
                'description' => array(
                    'title'       => __('Description', 'woocommerce'),
                    'type'        => 'textarea',
                    'description' => __('This controls the description which the user sees during checkout.', 'woocommerce'),
                    'default'     => 'Pay via LDFA Payment Gateway.',
                ),
                'app_id' => array(
                    'title'       => __('Live App ID', 'woocommerce'),
                    'type'        => 'text'
                ),
                'publishable_key' => array(
                    'title'       => __('Live Publish Key', 'woocommerce'),
                    'type'        => 'text'
                ),
                'merchant_key' => array(
                    'title'       => __('Live Merchant Key', 'woocommerce'),
                    'type'        => 'text'
                ),
                'cart_id' => array(
                    'title'       => __('Shopping Cart Key', 'woocommerce'),
                    'type'        => 'text'
                )
            );
        }

        
        public function payment_fields() {
            if ( $this->description ) {
                echo wpautop( wp_kses_post( $this->description ) );
            }
        }
        
        public function payment_scripts() {
            // Placeholder for including any necessary JavaScript files for the payment gateway
        }

        public function validate_fields() {
            if( empty( $_POST[ 'billing_first_name' ]) ) {
                wc_add_notice(  'First name is required!', 'error' );
                return false;
            }
            return true;
        }

        public function process_payment( $order_id ) {
            global $woocommerce;
            $order = wc_get_order( $order_id );

            $order->update_status('on-hold', __( 'Awaiting LDFA Payment Response', 'woocommerce' ));
            $woocommerce->cart->empty_cart();
            
            $status_file = get_site_url().'/wp-content/plugins/ldfa-gateway/templates/order_reciept.php';

            $orderDetails = json_encode(array('site_url' => $status_file, 'merchant_id' => $this->get_option( 'merchant_key' ), 'publish_key' => $this->get_option( 'publishable_key' ), 'order_id' => $order_id, 'total_cost' => $order->total));
            $finalOrder = base64_encode($orderDetails);
            return array(
                'result' => 'success',
                'order_id' => $order_id,
                'redirect' => get_site_url().'/wp-content/plugins/ldfa-gateway/ldfa-redirect.php?mt_r='.$finalOrder
            );
        }

        public function webhook() {
            // Placeholder for handling webhook requests
        }
    }
}

I am not getting option on checkout page

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