CountryField

use Bjanczak\FilamentFlexFields\Filament\Forms\Components\CountryField;

CountryField::make('country')
    ->label('Country')
    ->defaultCountry('PL')
    ->required();

use Bjanczak\FilamentFlexFields\Filament\Forms\Components\CountryField;

CountryField::make('shipping_country')
    ->countries(['PL', 'DE', 'GB', 'US', 'FR'])
    ->exceptCountries(['RU'])
    ->showCountryCode()
    ->browserLocaleDefault()
    ->browserLocaleSortFirst();

$record->country_code; // string|null — e.g. "PL", "US", "DE"

CountryField::make('country')
    ->countries(['US', 'CA', 'MX']);

CountryField::make('country')->showDialCode();

public static function form(Form $form): Form
{
    return $form->schema([
        CountryField::make('shipping_country')
            ->label('Delivery Country')
            ->countries(config('app.shipping_countries'))
            ->browserLocaleDefault()
            ->required(),
    ]);
}