Update README.md

README.md

@@ -21,6 +21,7 @@ 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)
 * [Usage](#usage)
 * [About us](#about-us)
     * [Community](#community)
@@ -54,6 +55,10 @@ This **open-source plugin was developed to help the Sylius community**. If you h
 
 Read more about  [BitBag Sylius Catalog Plugin](https://bitbag.io/blog/customize-sales-in-sylius-based-ecommerce-sylius-catalog-plugin/?utm_source=github&utm_medium=referral&utm_campaign=plugins_catalog)
 
+# Functionalities
+
+All main functionalities of the plugin are described [here.](https://github.com/BitBagCommerce/SyliusCatalogPlugin/blob/master/doc/functionalities.md)
+
 
 ## Usage