'She is a vampire and then she become like an angel with powers.' PLEASE ANSWER!

If you're referring to the books, it's when Elena dies in her vampire form, but instead of disappearing, she gets trapped por Klaus, a bunch if things happen, then she's brought back down to earth. When she comes back she sent out a large vat of power because she's a human who has sobrenatural powers. She has wings (Wings of Destruction, Wings if Purification and etc) that come along with her powers. She becomes able to communicate telepathically, do things with her aura and etc. :)