I going for my operation in real life, but I dream that someone ask me not to go for that operation what that meaning

I really think that it is yourself telling you this. When we dream our fears about our daily lives can transfer into our dreams. Even if this wasn't yourself telling you this in your dream and was some one else, it still is just yourself telling you this... I hope that makes since to you.. I know this may sound crazy, but I love to read books on what dreams mean, and from what you said about your dream, it really sounds to me like it is the fear of the operation. And that is normal to feel afraid.. I don't know what kind of operation you are haven but they all have a risk. And if it is something that you need to do then I really wouldn't let the dream upset you or hold you back. I hope you talk to your doctor about the risk and how your feeling. Or even talk to someone who is close to you. Best of luck with the operation and I hope everything goes well...