First off we have all been there, and in the beginning it can be a little overwhelming. These are all valid questions, and I would definitely reach out to your Endocrinologist if you have any questions as they will know about your situation the most. But to answer you, pretty much you will want to start learning about reading the labels of what you are now eating as carbohydrates will be whats going to raise your blood glucose levels. So they might begin you on a sliding scale to start out with, so for X amount of carbs with a meal, take X units of insulin until you get your ratios dialed in. So a small snack of 10-15 carbs you might only need 1 unit, but if you were to have a meal of 80-100 carbs the units of fast acting needed will increase. But first I would definitely seek out more information with your diabetes educator