In Code Protector, to license an application you first have to selected a Product Name in the Licensing option at the project level.
Once you have opted to license an application then when you select an individual method for protection, when you click the corresponding checkbox you are by default asked to associate the method with a correponding Unlocking Feature.
If you do not wish the method to be tied to a specfic unlocking feature in a license then leave Unlocking Feature set to the default value "EXECUTE".
This means that the protected method will execute provided any valid license is installed for the product. So you must have a license but any valid license will suffice to execute the method.