custom admin column

add_filter( 'manage_(post_type)_posts_columns', 'FUNCTION_NAME' );
function FUNCTION_NAME( $columns ){
	$newColumns = [
		'name_case' => 'Name column',
	];
	return array_slice( $columns, 0, 2 ) + $newColumns + $columns;
}

add_action( 'manage_(post_type)_posts_custom_column', 'FUNCTION_NAME', 10, 2 );
function FUNCTION_NAME( $column, $post_id ){
	switch( $column ){
		case 'name_case' :
			$email = get_post_meta(get_the_ID(), 'prefix_field', true);
			echo '<a href="mailto:'.$email.'">'.$email.'</a>';
			break;
	}
}