add_filter( 'woocommerce_checkout_fields' , 'custom_remove_woo_checkout_fields' );
 
function custom_remove_woo_checkout_fields( $fields ) {

    // remove billing fields
    unset($fields['billing']['billing_first_name']);
    unset($fields['billing']['billing_last_name']);
    unset($fields['billing']['billing_company']);
    unset($fields['billing']['billing_address_1']);
    unset($fields['billing']['billing_address_2']);
    unset($fields['billing']['billing_city']);
    unset($fields['billing']['billing_postcode']);
    unset($fields['billing']['billing_country']);
    unset($fields['billing']['billing_state']);
    unset($fields['billing']['billing_phone']);
    unset($fields['billing']['billing_email']);
   
    // remove shipping fields 
    unset($fields['shipping']['shipping_first_name']);    
    unset($fields['shipping']['shipping_last_name']);  
    unset($fields['shipping']['shipping_company']);
    unset($fields['shipping']['shipping_address_1']);
    unset($fields['shipping']['shipping_address_2']);
    unset($fields['shipping']['shipping_city']);
    unset($fields['shipping']['shipping_postcode']);
    unset($fields['shipping']['shipping_country']);
    unset($fields['shipping']['shipping_state']);
    
    // remove order comment fields
    unset($fields['order']['order_comments']);
    
    return $fields;
}