i want to knw if theres a security option where in i can control the opposite person frm not takin my picture or vedio without my knowledge while im vedio chattin wit them over skype!!!!!!!
No, there's no way to do that.
Even if there were a way to prevent taking a photo of you on someone's computer during a video call (which there isn't) if they wanted badly enough to take your photo, what would stop them from taking a photo of their computer screen with a camera? Nothing, of course.
My suggestion is if you don't trust someone, don't have a video call with them.