Welcome to the site!
First things first. You cannot be a Christian Wiccan; they are two opposing religions.
Magic itself has no colour, but using magic for evil purposes would be considered "black"; done for good and healing, "white".It is how the magic is intended, not the magic.
Magic means different things to different beliefs. However, if you practise magic in whatever form, then you are a witch.There are different "labels", Hedge Witch, Heathen, Kitchen Witch, Etc., depending on the type of magic you practise.But they are just labels of particular practise; it is all witchcraft.
The "Basics" are the same; Meditation,Grounding; Centering.