How do I a custom search form by taxonomies?

Question

Im new in this of Wordpress, and I need to create a custom search form by Taxonomies, like a dropdown filter. Can u help me? Im just have the Searchform.php and this code for a Basic Search bar

<?php

<form role="search" method="get" class="form-inline my-2 my-lg-0" action="<?php echo esc_url( home_url('/')); ?>">

    <input class="form-control mr-sm-2" type="search" placeholder="Buscar" aria-label="Search">

    <button class="btn btn-outline-success my-2 my-sm-0" type="submit">Buscar</button>

</form>`