Raymondo, you may just have to accept the fact that most people believe the Earth to be round, if nothing else. When claiming the Earth is flat, there is a good chance people won't be supportive. It wouldn't be a bad idea to have your brother teach you the evidence, which supports the widely accepted theory of which the Earth is round. I don't mean to say that you should abandon our frame of thought, I only think you should educate yourself better. If you do, I think you would be able to defend yourself better.