update readme file

Author: dipudey

README.md

@@ -3,3 +3,71 @@
 </p>
 
  <h1 align="center">uPay BD Payment Gateway</h1>
+<p align="center" >
+<img src="https://img.shields.io/packagist/dt/codeboxr/upay">
+<img src="https://img.shields.io/packagist/stars/codeboxr/upay">
+</p>
+## Requirements
+
+- PHP >=7.2
+- Laravel >= 6
+
+## Installation
+
+```bash
+composer require codeboxr/upay
+```
+
+### vendor publish (config)
+```bash
+php artisan vendor:publish --provider="Codeboxr\Upay\UpayServiceProvider"
+```
+
+After publish config file setup your credential. you can see this in your config directory upay.php file
+```
+"sandbox"                => env("UPAY_SANDBOX", false), // for production use true
+"merchant_id"            => env("UPAY_MERCHANT_ID", ""),
+"merchant_key"           => env("UPAY_MERCHANT_KEY", ""),
+"merchant_code"          => env("UPAY_MERCHANT_CODE", ""),
+"merchant_name"          => env("UPAY_MERCHANT_NAME", ""),
+"merchant_mobile"        => env("UPAY_MERCHANT_MOBILE", ""),
+"merchant_city"          => env("UPAY_MERCHANT_CITY", ""),
+"merchant_category_code" => env("UPAY_CATEGORY_CODE", "9399"),
+"redirect_url"           => env("UPAY_CALLBACK_URL", "")
+```
+
+## Usage
+
+### 1. Create Payment
+
+```
+use Codeboxr\Upay\Facade\Payment;
+
+return Payment::executePayment($amount, $invoiceId, $txnId, $date);
+
+```
+### Example
+
+```
+return Payment::executePayment(10, 'CBX10101', '10127373', '2022-08-26');
+```
+### 2. Query Payment
+
+```
+use Codeboxr\Upay\Facade\Payment;
+
+Payment::queryPayment($invoiceId); // Invoice ID 
+```
+
+## Contributing
+
+Contributions to the uPay package are welcome. Please note the following guidelines before submitting your pull request.
+
+- Follow [PSR-4](http://www.php-fig.org/psr/psr-4/) coding standards.
+- Read uPay API documentations first
+
+## License
+
+uPay package is licensed under the [MIT License](http://opensource.org/licenses/MIT).
+
+Copyright 2022 [Codeboxr](https://codeboxr.com)