how to implement scheduler in auto hosted windows service

Question

i want to add timer that will import excel or csv file in navision at the end of the month the code is done only thing left is to add timer but i could not find any solution.

using WorkHoursImporterWinService;

IHost host = Host.CreateDefaultBuilder(args)
    .UseWindowsService()
    .ConfigureAppConfiguration((context, config) =>
    {
        // configure the app here

    })
    .ConfigureServices(services =>
    {
        services.AddHostedService<Worker>();
    })
    .Build();

await host.RunAsync();