Creating a Project with Visual Studio:

* Remove unnecessary code snippet, to make code more simplified

DutchTreat/Startup.cs

@@ -21,19 +21,9 @@ namespace DutchTreat
         // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
         public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
         {
-            if (env.IsDevelopment())
+            app.Run(async context =>
             {
-                app.UseDeveloperExceptionPage();
+                await context.Response.WriteAsync("Hello World!");
-            }
-
-            app.UseRouting();
-
-            app.UseEndpoints(endpoints =>
-            {
-                endpoints.MapGet("/", async context =>
-                {
-                    await context.Response.WriteAsync("Hello World!");
-                });
             });
         }
     }