• clone repository
• launch solution by Visual Studio 2019
• open packge manager console
• change default project to DateSelector.API
• run command update-database
• run API project
• you can access to the project swagger via url /swagger/index.html

• run your API project
• copy url of your localhost
• open HttpCaller class
• change _apiUrl constant with copied url.
• run console application project

The rest of Caller project is pretty self descriptive.

• you can find connection string in appsettings.Development.json file
• in Microsoft SQL Server Management use Windows Authentication and default (localdb)\MSSQLLocalDB Server name
• default database name - DateSelectorDB

If you successfully configure API you should see two default row in database. First is range withing current day and tomorrow. Second - today and (today + 10 days). These two together with Swagger support were provided just for demonstration purpose.