Authenticating a console application using modern authentication

Question

A C# console application which runs like a background job from Windows Task Scheduler is using simple authentication with hardcoded username and password to connect to Sharepoint.

This application downloads list of sites from Sharepoint and creates a file in a folder. I have been asked to replace the simple authentication with any modern authentication. I googled around and found that I need an authentication without interactive browser since it is a background job.

I found below code and also want to try out on a machine which does not have Microsoft Identity and Sharepoint license. So I have two questions here:

1. Is the below code sufficient to authenticate without interactive browser ?

2. I want to buy Microsoft 365 Basic license. It shows under included list Identity, Sharepoint etc. Are these sufficient to try out below code ?

Code:

using System;
using System.Net.Http;
using System.Threading.Tasks;
using Microsoft.Graph;
using Microsoft.Identity.Client;

class Program
{
   private static async Task Main(string[] args)
   {
       string tenantId = "YOUR_TENANT_ID";
       string clientId = "YOUR_CLIENT_ID";
       string clientSecret = "YOUR_CLIENT_SECRET";

       var scopes = new[] { "https://graph.microsoft.com/.default" };

       // Create an authentication provider
       var confidentialClient = ConfidentialClientApplicationBuilder
           .Create(clientId)
           .WithClientSecret(clientSecret)
           .WithAuthority($"https://login.microsoftonline.com/{tenantId}")
           .Build();

       var authProvider = new DelegateAuthenticationProvider(async (requestMessage) =>
       {
           var authResult = await confidentialClient.AcquireTokenForClient(scopes).ExecuteAsync();
           requestMessage.Headers.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("Bearer", authResult.AccessToken);
       });

       // Create GraphServiceClient
       var graphClient = new GraphServiceClient(authProvider);

       // Fetch SharePoint site details
       await GetSharePointSite(graphClient);
   }

   private static async Task GetSharePointSite(GraphServiceClient graphClient)
   {
       try
       {
           var site = await graphClient.Sites["contoso.sharepoint.com"].Request().GetAsync();
           Console.WriteLine($"Site ID: {site.Id}");
           Console.WriteLine($"Site Name: {site.DisplayName}");
       }
       catch (Exception ex)
       {
           Console.WriteLine($"Error: {ex.Message}");
       }
   }
}