Get SharePoint Online Tenant Properties using CSOM

GetTenantPropsCSOM.cs

using Microsoft.SharePoint.Client;
using OfficeDevPnP.Core;
using System;

namespace TenantProps
{
    class Program
    {
        static void Main(string[] args)
        {
            //This can be any site in the tenant
            string siteUrl = "https://tenant.sharepoint.com/sites/intranet";

            var clientContext = GetAppOnlyClientContext(siteUrl);
   
            var web = clientContext.Web;

            var tenantProperty = web.GetStorageEntity("mykey1");

            clientContext.Load(tenantProperty);

            clientContext.ExecuteQuery();

            Console.WriteLine($"{tenantProperty.Value},{tenantProperty.Comment},{tenantProperty.Description}");
            Console.ReadKey();
        }
        
        //Using App Only Client Context with SharePoint Authentication. You can use other ways to get the ClientContext as well.
        private static ClientContext GetAppOnlyClientContext(string siteUrl)
        {
            //Part of OfficeDevPnP.Core
            var authManager = new AuthenticationManager();
            //https://docs.microsoft.com/en-us/sharepoint/dev/solution-guidance/security-apponly-azureacs
            return authManager.GetAppOnlyAuthenticatedContext(siteUrl, "<client-id>", "<client-secret>");
        }
    }
}

Hi, what is the alternate for above. Currently we are getting 'The remote server returned an error: (403) Forbidden.'. We want get context using "client-id", "client-secret", siteurl.