i am a student of class 9 of cms i failed in class 9.i should repeat it or find any other school.i am also weak in pcm.i can take com/eco

i am not very weak but according to science i am very weak.and my percentage had never cross more than 35 which i have got in class 7 so please tell me what should i take science or commerce.if science how i have to study?should i repeat 9 to improve my 10 result?