Update README.md

Author: LadyNaggaga

README.md

@@ -33,7 +33,7 @@ To make your Markdown files interactive, you will need the [.NET Core 3.0 SDK](h
 ## Setup
 
 Before you get can start creating interactive documentation, you will need to install the following: 
-- [.NET Core 3.0 SDK](https://dotnet.microsoft.com/download/dotnet-core/3.0)
+- [.NET Core 3.0 SDK](https://dotnet.microsoft.com/download/dotnet-core/3.0)and [2.1](https://dotnet.microsoft.com/download/dotnet-core/2.1) currently dotnet try global tool targets 2.1. 
 - [dotnet try global tool] (*coming soon*)
 Once you have successfully installed `dotnet try`, enter the command `dotnet try -h` to see a list of commands: