Date of arrival and date of depart

Hello,
i would like to know how i can set the minimum date from the field ” Date of departure”
to the value ” Date of arrival + 1day”
actually ,it works because i use the plugin “Contact Form 7 Datepicker” and i put this in my functions.php:

// WordPress custom function
function my_custom_function(){
    ?>
    <script>
jQuery(function($){

    jQuery("#date1").datepicker({
        dateFormat: 'dd/mm/yy',
        onSelect    : function (selected) {
            var unique = jQuery(this).attr('id');
            unique = unique.replace('date1', '');
            var date = jQuery(this).datepicker('getDate');
            if (date) {
                date.setDate(date.getDate()  + 1);
            }
            jQuery( '#date2' + unique).datepicker( 'option', 'minDate', date)
        }
    });
});
    </script>
    <?php
}
add_action('wp_footer', 'my_custom_function');

Is there a way to do this without the plugin “Contact Form 7 Datepicker” ?

Thanks for your answer!

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