Need help in exercise/body building...?

I recommend doing different kinds of push ups to develop the muscles in your arms and chest. You can do close hand where you form a triangle shape with your hands close together, wide arm push ups and regular ones. This helped me grow a nice chest even though I'm still very lean. For your legs you can simply stand on your your tip toes then come down, I do this about 50 times until my legs get tired. Just look on youtube for exercises you can do with the weights. Good luck.