Disable WooCommerce Checkout

disable-wc-checkout.php

<?php

add_action( 'init', function() {

   remove_action( 'woocommerce_after_shop_loop_item', 'woocommerce_template_loop_add_to_cart', 10 );
   remove_action( 'woocommerce_single_product_summary', 'woocommerce_template_single_add_to_cart', 30 );
   remove_action( 'woocommerce_proceed_to_checkout', 'woocommerce_button_proceed_to_checkout', 20 );
   remove_action( 'woocommerce_checkout_order_review', 'woocommerce_checkout_payment', 20 );
   add_action( 'woocommerce_before_main_content', 'resknow_show_checkout_disable_notice', 5 );
   add_action( 'woocommerce_before_cart', 'resknow_show_checkout_disable_notice', 5 );
   add_action( 'woocommerce_before_checkout_form', 'resknow_show_checkout_disable_notice', 5 );
  
} );

function resknow_show_checkout_disable_notice() {
  
  wc_print_notice( 'We\'re no longer taking online orders, please contact us to discuss your requirements.', 'error');
  
}