I am a 18 yo male and I started going to the gym. I have only 3 days/week for working out. I am a combination of skinny, fat and muscle:)) I stand at 1,76 meters and I weight 68 kg. I decided to do: -1st day: back; -2nd day: legs and abs; -3rd day: shoulders, traps and forearm; Do you think it's enough for building some muscle? Or should I add chest day? Or maybe can I include only pushups at home as chest day?

EDIT: I have scoliosis, and kyphosis and my doctor recommended me to do either swimming or light weight exercises at gym. So, I want to strenghten my back and also to achieve a nice muscular body but not with heavy weights...