Updated the README file

Author: saravanangn

README.md

@@ -1,2 +1,23 @@
 # Cascading-Dropdown-List-in-Blazor-using-Entity-Framework
 Cascading Dropdown List in Blazor using Entity Framework, The cascading Dropdown List is a series of Dropdown List, where the value of one Dropdown List depends upon another’s value.
+
+## Project pre-requisites
+Make sure that you have the compatible versions of Visual Studio Code and .NET Core SDK 3.1.2 in your machine before starting to work on this project.
+
+## How to run this application?
+To run this application, you need to first clone the `getting-started-with-blazor-dropdown-list` repository and then open it in Visual Studio Code. 
+
+* Need to change the Database connection string in Shared/DataAccess/DataContext.cs
+
+```
+optionsBuilder.UseSqlServer(@"Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename=D:\DropDownList\EFDropDown\Shared\App_Data\NORTHWND.MDF;Integrated Security=True;Connect Timeout=30");
+
+```
+
+* Now, open the `Integrated Terminal` in VS Code and run the following command to build and run this project.
+
+```
+dotnet watch run
+```
+
+Navigate to `http://localhost:5000/` or `http://localhost:5001/` in the browser to view the output.