Grouping data in LINQ (Group By) — how to correctly group a list of objects?

Hello everyone! I'm a beginner in C# and trying to understand data grouping using LINQ. I have a list of orders in an online store. Each order contains a client ID, product name, and amount. I need to display for each client a list of their orders and the total amount of their purchases. I've heard about the GroupBy method, but I can't figure out how to use it correctly. Here's an example of my class and data: ```csharp public class Order { public int ClientId { get; set; } public string ProductName { get; set; } public decimal Amount { get; set; } } List orders = new List { new Order { ClientId = 1, ProductName = "Laptop", Amount = 50000 }, new Order { ClientId = 2, ProductName = "Mouse", Amount = 1500 }, new Order { ClientId = 1, ProductName = "Keyboard", Amount = 3000 }, new Order { ClientId = 3, ProductName = "Monitor", Amount = 25000 }, new Order { ClientId = 2, ProductName = "Mousepad", Amount = 500 } }; ``` I tried to write something