GetValue to read the configuration settings

HomeController.cs

public class HomeController : Controller
{
    private readonly ILogger<HomeController> _logger;
    private readonly IConfiguration configuration;

    public HomeController(ILogger<HomeController> logger, IConfiguration configuration)
    {
        _logger = logger;
        this.configuration = configuration;
    }

    public IActionResult Index()
    {
        var mode = configuration.GetValue<string>("Mode", "default-mode");
        var defaultLogLevel = configuration.GetValue<string>("Logging:LogLevel:Default", "Info");
        var firstSubjectFromArray = configuration.GetValue<string>("MailFeature:0:Subject", "unknown");
        return View();
    }
}