To add a search bar at the top of the sidebar in your GeneratePress websit

gistfile1.txt

// Add search bar to the top of the sidebar
function add_search_bar_to_sidebar() {
    ?>
    <div class="custom-sidebar-search">
        <?php get_search_form(); ?>
    </div>
    <?php
}
add_action('generate_before_sidebar_content', 'add_search_bar_to_sidebar');

i added this code to my site (https://7brewcoffemenu.com/ please check the sample