If & when I am aable to evoke a spirit, how do I ntroduce myself? Do I say my real name, do I need to have a magickal name? And if so, how to get it?
You don’t need a magical name. You can develop one if you want to. Mine of instance is a sigilized statement of intent that I use in ritual.
Sometimes spirits may call you by a different name and that is always fun to figure out what they mean. (Example Jason Miller was given Inominandum)