Could you tell us about required fix please

<?php
	
				$estimated_text = WC()->customer->is_customer_outside_base() && ! WC()->customer->has_calculated_shipping()
					? sprintf( ' ' . __( ' (taxes estimated for %s)', 'theme-name' ), WC()->countries->estimated_for_prefix() . __( WC()->countries->countries[ WC()->countries->get_base_country() ], 'theme-name' ) )
					: '';
	
				printf( __( 'Note: Shipping and taxes are estimated%s and will be updated during checkout based on your billing and shipping information.', 'theme-name' ), $estimated_text );
	
			?>

getting the following error

Found a translation function that is missing a text-domain. Function __, with the arguments

2nd

fopen was found in the file subscribe_save.php File operations should use the WP_Filesystem methods instead of direct PHP filesystem calls.

$fp = fopen('subscribers.csv', 'w');
what would be the correct line ?

fclose was found in the file subscribe_save.php File operations should use the WP_Filesystem methods instead of direct PHP filesystem calls

fclose($fp);

last but not least ” The theme uses the add_shortcode() function. Custom post-content shortcodes are plugin-territory functionality.”

we are using add_shortcode() through out the theme any solution to fix this issue ?