You can store encrypted values in your ASP.NET Core configuration file and seamlessly decrypt the values as you retrieve them. But there are, at least, two issues that you'll need to address.

Take advantage of connection resiliency in EF Core to detect errors and retry commands and enable your ASP.NET Core application to overcome transient faults.

Take advantage of user secrets management in ASP.NET Core to prevent the sharing of sensitive application data in your projects When working with ASP.NET web applications, you will want to protect ...