i would personally avoid Silver Ravenwolf as she is a rather controversial writer. though To Ride a Silver Broomstick is one of her better works. I suggest you read a beginners guide by Scott Cunningham or Raymond Buckland.
anyway, to answer your questions:
Is magic real?
yes magick is real. there is a difference between the magic you see in movies and the magick you would cast. real magick is more spiritual and deals in the realms of nature to effect ones life. if it goes against nature, it can't be done. [like flying or transformation] to quote Scott Cunningham: "magic is the movement of natural (yet subtle) energies to manifest positive, needed change. Magic is the process of 'rousing' energy, giving it purpose (through visualization) and releasing it to create a change. This is a natural (not supernatural) practice."
can you see it?
not always. sometimes some people can see the energy as they charge it, but you can't see sparkles or glowing as you cast a spell. you can feel the energy, some people can see or hear it, but typically it is felt. you must then visualize the desired outcome of your spell.
how come my dreams actualy become real? is dejavu realy exsists or is it something else?
Deja vu is real in my opinion, i don't know what the official stance is. it's just a feeling you'll get when a situation seems familiar. i use to get it a lot as a child. dreams coming true are called Prophetic dreams, where your mind picks up on subtle cues in life and tries to tell you through symbols in your dreams, or your clairvoyant abilities will show you glimpses of the future. prophetic dreams usually reoccur until the event transpires, then will never be had again. it sometimes will be every night, but the ones i have, and the ones most i speak to typically come every so many weeks, or months, or sometimes once a year. when you have a reoccurring dream, or a rather vivid dream, you should write it down in interpret it, in case there's any warning you should heed.
I found that it said witches are woman that had relation ships with the fallen angels a long time ago, is that real?
no. it's an old wives tale, not real. a witch can be male or female, and is a person who works magick, or follows a more natural path, but spellcasting of some sort is usually involved. if not, some form of herbalism or other practice. when Christianity became a leading religion, they wanted people to turn away from the old paths, so these types of tales began to surface, just as a way to deter people from affiliating with those who followed pagan faiths. [also, while it's cool your great-grandmother was a witch, it doesn't mean you are one. you might have some special gift, like prophetic dreams, but to become a witch is a choice, and it involves years of study, you're not actually born one.]