How to Customize The Search Form – WordPress

Just create a searchform.php file in your theme folder and put the below form code in it.

<form method="get" id="searchform" action="<?php echo esc_url( home_url( '/' ) ); ?>">
  <input placeholder="Search..." type="search" class="field" autocomplete="off" id="s" name="s" value="">
  <input type="submit" class="submit" name="submit" id="searchsubmit" value="<?php esc_attr_e( 'SEARCH', 'Submit Button' ); ?>" />
</form>