ConfigurationBuilder does not contain a definition for SetBasePath

In this article we will see how to solve issue 'ConfigurationBuilder' does not contain a definition for 'SetBasePath' and no extension method 'SetBasePath' accepting a first argument of type 'ConfigurationBuilder' could be found (are you missing a using directive or an assembly reference? in .Net Core 3. We will see how to ready json files in .Net core 3.