JSFiddle - React, Tailwind, and code Playground

HTML

<div ng-app="myApp">
<div ng-controller="testController">
        <select name="client" ng-model="selectedRequest.continent" ng-options="c.name.en for c in clients.brandList" required></select>
        <select id="department" ng-model="selectedRequest.state" ng-options="d.name.en for d in  selectedRequest.continent.children"></select>
    </div>
</div>

JavaScript

angular.module("myApp", []);
function testController($scope) {
            $scope.clients = {
    "brandList": [{
        "name": {
            "en": "Benz"
        },
        "type": "Benz",
        "children": [{
            
            "name": {
                "en": "Regular"
            }
        }, {
            
            "name": {
                "en": "Truck"
            }
        }]
    }, {
        "name": {
            "en": "Ferrari"
        },
        "type": "Ferrari",
        "children": [

        ]
    }]
};

             $scope.selectedRequest = {};
            
        }