How to validate array in Request rules laravel?

Based on your json you can do something like below

public function rules()
{
    return [
        'name'           => 'required',
        'dial_number'    =>  'required',
        'phone_number'   => 'required|array',
        'phone_number.number' => 'required|regex:/(^[0-9 ]+$)+/',
        'phone_number.internationalNumber' => 'required|regex:/(^[0-9 ]+$)+/',
        'phone_number.nationalNumber' => 'required|regex:/(^[0-9 ]+$)+/',
        'phone_number.e164Number' => 'required',
        'phone_number.countryCode' => 'required|string',
        'phone_number.countryCode' => 'required|string',
        'phone_number.dialCode' => 'required',
        //'image'           =>  'required',
    ];
}

for more info you can visit laravel documentation