Are C# properties actually Methods?

Yes, the compiler generates a pair of get and set methods for a property, plus a private backing field for an auto-implemented property.

public int Age {get; set;}

becomes the equivalent of:

private int <Age>k__BackingField;

public int get_Age()
{
     return <Age>k__BackingField;
}

public void set_Age(int age)
{
    <Age>k__BackingField = age;
}

Code that accesses your property will be compiled to call one of these two methods. This is exactly one of the reasons why changing a public field to be a public property is a breaking change.

See Jon Skeet’s Why Properties Matter.