Update README.md

README.md

@@ -17,6 +17,7 @@ Like what we do? Want to join us? Check out our job listings on our [career page
 
 * [Overview](#overview)
 * [Support](#we-are-here-to-help)
+* [Functionalities](#functionalities)
 * [Installation](#installation)
    * [Cron job](#cron-job)
    * [Fixtures](#Fixtures)
@@ -36,6 +37,10 @@ This **open-source plugin was developed to help the Sylius community**. If you h
 
 [![](https://bitbag.io/wp-content/uploads/2020/10/button-contact.png)](https://bitbag.io/contact-us/?utm_source=github&utm_medium=referral&utm_campaign=plugins_amazon_pay)
 
+# Functionalities
+
+All main functionalities of the plugin are described [here.](https://github.com/BitBagCommerce/SyliusAmazonPayPlugin/blob/master/doc/functionalities.md)
+
 
 # Installation