carb exchange

Hello, I have been type 1 diabetic for 20 years but I havent learned about carb counting. I mostly used gramms to calculate novorapid units. For example Morning : 100 gr bread + a glass of milk ( I inject 6 units novorapid) Lunch: 400 gr carbs(macaronni, rice, potatoes e.t.c.)+ 100 gr meat or...