You're only 13 and your dad is saying this stuff about you and your teacher! I know everyone is probably telling you this but just be careful of what you eat. If you want start off with light exercises. Go see you doc and tell them to give you a diet if you want i can give you a diet that a doctor gave my mom. You'll lose 52 pounds in 2 and a half months. That's only if you want. You can email me at twinkle_starry@hotmail.com and i'll give it to you. the starry is not a typo some people may think that but yes it's not it's twinkle_starry@hotmail.com