How to use wp_dropdown_pages or wp_list_pages to accomplish a menu like this?

Here’s an easy way to generate a dropdown menu from your blog pages using the WordPress wp_dropdown_pages() function.

Adding a bit of javascript you can send the user to the page when they select it

  <section id="pageselect">
                <span>
                <?php wp_dropdown_pages('show_option_none=Explore...'); ?>
                </span>
                <script type="text/javascript"><!--
                    var selectmenu = document.getElementById("page_id");
                    function onPageChange() {
                        if ( selectmenu.options[selectmenu.selectedIndex].value > 0 ) {
                            location.href = "https://wordpress.stackexchange.com/questions/268921/<?php echo get_option("home'); ?>/?page_id="+selectmenu.options[selectmenu.selectedIndex].value;
                        }
                    }
                    selectmenu.onchange = onPageChange;
                --></script>
    </section><!-- end pageselect -->