Properties and Indexers - General Questions

What does an init accessor (C# 9) allow?

What is an indexer?

What is the advantage of properties over public fields?

What is the output of the following program?

var p = new Product { Price = 120 };
Console.WriteLine(p.Price);
class Product { public int Price { get; set; } }

What is the output of the following program?

var u = new User { Name = "Ravi" };
Console.WriteLine(u.Name.Length);
class User { public string Name { get; init; } = ""; }