Install VueJS in Laravel 8

@Sinnbeck Thanks. Here is my Composer.json.

{
    "name": "laravel/laravel",
    "type": "project",
    "description": "The Laravel Framework.",
    "keywords": ["framework", "laravel"],
    "license": "MIT",
    "require": {
        "php": "^7.3|^8.0",
        "ext-curl": "*",
        "ext-json": "*",
        "barryvdh/laravel-cors": "^2.0",
        "brian2694/laravel-toastr": "^5.54",
        "doctrine/dbal": "^3.3",
        "fideloper/proxy": "^4.4",
        "fruitcake/laravel-cors": "^2.0",
        "google/apiclient": "^2.0",
        "gregwar/captcha": "^1.1",
        "grimzy/laravel-mysql-spatial": "5.0",
        "guzzlehttp/guzzle": "^7.0.1",
        "intervention/image": "^2.5",
        "kingflamez/laravelrave": "^4.2",
        "laravel/framework": "^8.12",
        "laravel/passport": "^10.1",
        "laravel/tinker": "^2.5",
        "laravel/ui": "*",
        "laravelpkg/laravelchk": "dev-master",
        "madnest/madzipper": "*",
        "mercadopago/dx-php": "2.4.3",
        "nexmo/laravel": "^2.4",
        "paypal/rest-api-sdk-php": "^1.14",
        "rap2hpoutre/fast-excel": "^3.0",
        "razorpay/razorpay": "^2.5",
        "stripe/stripe-php": "^7.77",
        "twilio/sdk": "^6.28",
        "unicodeveloper/laravel-paystack": "1.0.*"
    },
    "require-dev": {
        "barryvdh/laravel-debugbar": "^3.5",
        "facade/ignition": "^2.5",
        "fakerphp/faker": "^1.9.1",
        "laravel/sail": "^1.0.1",
        "mockery/mockery": "^1.4.2",
        "nunomaduro/collision": "^5.0",
        "phpunit/phpunit": "^9.3.3"
    },
    "autoload": {
        "files": [
            "app/Helper_Functions.php",
            "app/CentralLogics/banner.php",
            "app/CentralLogics/cuisine.php",
            "app/CentralLogics/category.php",
            "app/CentralLogics/campaign.php",
            "app/CentralLogics/product.php",
            "app/CentralLogics/restaurant.php",
            "app/CentralLogics/helpers.php",
            "app/CentralLogics/order.php",
            "app/CentralLogics/coupon.php",
            "app/CentralLogics/sms_module.php",
            "app/CentralLogics/filemanager.php",
            "vendor/laravelpkg/laravelchk/src/Http/Controllers/LaravelchkController.php"
        ],
        "psr-4": {
            "App\": "app/",
            "Database\Factories\": "database/factories/",
            "Database\Seeders\": "database/seeders/"
        }
    },
    "autoload-dev": {
        "psr-4": {
            "Tests\": "tests/"
        }
    },
    "scripts": {
        "post-autoload-dump": [
            "Illuminate\Foundation\ComposerScripts::postAutoloadDump",
            "@php artisan package:discover --ansi"
        ],
        "post-root-package-install": [
            "@php -r \"file_exists('.env') || copy('.env.example', '.env');\""
        ],
        "post-create-project-cmd": [
            "@php artisan key:generate --ansi"
        ]
    },
    "extra": {
        "laravel": {
            "dont-discover": []
        }
    },
    "config": {
        "platform-check": false,
        "optimize-autoloader": true,
        "preferred-install": "dist",
        "sort-packages": true,
        "allow-plugins": {
            "composer/package-versions-deprecated": true
        }
    },
    "minimum-stability": "dev",
    "prefer-stable": true
}

@afoysal ok you are running an old laravel version. Try

composer require laravel/ui ^3.0

//or
composer require laravel/ui ^2.0