I would contact Donovan support about this. The appearance of search boxes is the responsibility of the theme.
This is your code and I want to put it nel mio iPhone on the right in the bar near the menu button, can you tell me where to put it? Donovan theme.
https://snipboard.io/oO1lwx.jpg
<?php
add_filter( 'wp_nav_menu_items','add_search_box', 10 );
function add_search_box( $items ) {
$items .= '<li>' . get_search_form( false ) . '</li>';
return $items;
}
?>
Filter functions like this can go almost anywhere. If Donovan gets updates, don’t put it in the theme, otherwise it’ll be deleted in the next update. You can use a code snippet plugin for this. Another option is to use a child theme, in which case this would go to the child theme functions.php.