How do I turn this form into a search form? [closed]

Please try this ,

<form name="searchBox" action="<?php echo get_bloginfo('url'); ?>" class="search-form" method="get" role="search" >
        <input type="text" name="s" class="searchBox" placeholder="search" value="<?= $_GET['s'] ?>" required />
         <button type="submit" class="searchBtn" >search</button>
                  </form>