App.config debug and relase

Hello can anyone tell me how to rebuild the debug.appconfig and the relase.appconfig bcuz ill need them on my project to run it and i'll have a problem with db connstring here is my db code

Code:

---

    <connectionStrings>
      <!-- database connection string -->
      <add name="dentnedEntities" connectionString="Data Source=DESKTOP-Q8526KR/SQLEXPRESS;Initial Catalog=dentned;Integrated Security=true;" providerName="System.Data.EntityClient"/>
    </connectionStrings>

---

Check this out:

https://mitasoft.wordpress.com/2011/...ipleappconfig/

This is c# application that uses web interfaces and i'll need to create just the relase and debug config to complete my project and run it.