Lisa;
Welcome to the Forum!
The answer to most of your questions can be found in the
"GB Help" thread.
Adding Foods:
The food entries are a bit different from the blood glucose entries. Under Add Logs; Food; Add Food; Add Log; Create a food called Carbs. (grams), then pick that food each time you input your food. This method is very simple and lets you keep up with your food by logging carbs. However, to effectively use this method, you will need to learn to carb count. Please reference Carb Counting 101.
The food unit is Carb (grams).
I hope that all your medical problems work out for the best. Good luck with your control and management.