I came to know that a batsman can be stumped out off a wide ball but not off a no-ball (Is it correct?)
What are the possibilities to dismiss batsmen, off a noball, a wide ball, a freehit ball and two or three pitched(dead)ball?
Yes, you are right when you say that a batsman can be stumped off a wide but not off a no-ball.
Law 21.7 states that,
Ball bouncing more than once or rolling along the ground
The umpire shall call and signal No ball if a ball which he/she considers to have been delivered, without having previously touched bat or person of the striker, bounces more than once or rolls along the ground before it reaches the popping crease
So, in such cases the delivery is considered a no-ball and the same rules of a no-ball apply.