Dependent Dropdowns: Parent-Child

In our QuickAdminPanel generator, we don't have such feature like parent-child dropdowns, for example Country-City relationship where change of Country value refreshes the values of Cities.
However, you can build it yourself quite easily - we have a blog article for you: Laravel Forms: Select Dependent Dropdowns with jQuery and AJAX
In summary, you need to add jQuery code with AJAX call, similar to this:
<script type="text/javascript">
url: "{{ route('admin.cities.get_by_country') }}?country_id=" + $(this).val(),
method: 'GET',
success: function(data) {
Read more details in the article above.