Found the solution. The namespace was called Enum, and thus interferred the Enum in the System. So I changed the namespace and Enum.Parse worked perfectly
Other than Mosh you named your namespace Enum so this name overlays the imported class name. Whenever you use an unqualified identifier the compiler uses the declaration closest to the scope in which you use it.
You can still use the qualified name System.Emum to use the Enum class.