How can get Response from API when status is 4xx using Curl library

Are you talking about CURLRequest?
See https://codeigniter.com/user_guide/libra...ttp-errors

yes, its about it.
but how to get response from API when its status code is 400, 401

I use try-catch, but in catch cant use like Guzzle

PHP Code:

try {
    $response = $client->request('GET', 'http://example.com/api-endpoint');
    echo $response->getBody();
} catch (RequestException $e) {
    // check response if fail cause some reason
    if ($e->hasResponse()) {
        $response = $e->getResponse();
        echo 'HTTP Status Code: ' . $response->getStatusCode() . "\n";
        echo 'Response Body: ' . $response->getBody();
    } else {
        echo 'Request exception occurred without a response';
    }
}