That's really ridiculous to tell your brother to stop being social because you aren't. You can't seriously believe it even makes any sense at all! Your brothers behavior or social skills have nothing to do with you (unless he abuses you).

What do you mean by everyone preferring your brother. Does everyone even know him? You aren't even the same age. Why don't you have your own friends and circle? Many of my friends barely even know my brother (maybe meet at big events but not to hang out). Find a different circle of people.