You bring up several points; your A1c level and dieting. I'll repspond as best as I can to each.
A1c of 8.4%
This means your daily glucose [blood sugar] is 194 mg/dl, or close to twice the level above non-diabetics.For t2 diabetics you want your morning fasting levels
as close to normal as possible, where normal is <99 mg/dl. After meals levels should be <141 mg/dl, optimum <121 mg/dl. Don't believe the mumble jumbo of drug mfg sponsored web sites - like the ADA - touting after meal levels of 181 mg/dl as being acceptable. The higher your levels, the more drugs you need, the more drugs you need, the more $$$ drug companies make.
What needs to be done is a lifestyle change; proper nutrition, maintain normal body weight and BMI, perform 30 minutes of daily physical exercise like walking, keep good levels of cholesterol and triglycerides, and blood pressure.
I dislike the word diet as it implies a negative connotation. Try to focus on what you should eat, not what you shouldn't eat. Once you understand the foods to avoid make it into a challenging game to find foods that are good for you and will help lower your diabetic condition. I'll start with the bad, foods to avoid then point you towards to some goals.
Avoid white foods like potatoes, white rice, foods made with white flour - breads, crackers, muffins, donuts, pasta, etc. After digestion the sugar in these foods quickly enter your blood stream, thus jacking up your glucose levels. Pay careful attention to starchy foods too. Eat fruits with other foods to slow the absorption of fructose [fruit sugar]. But be careful, there are folks that cannot tolerate any fruits at all. [See below about testing]
Our body needs carbohydrates for energy and two types of carbs exist, the bad is called Simple carbs, the good is called Complex carbs. White foods belong in the Simple carb family. Use Google to search on "Simple vs Complex carbs" and also the Glycemic Index to get a good understannding. If you limit your carb intake you essentially are limiting you sugar intake. Eat lean meats, poultry and fish with lots of vegetables. Eat whole grains - foods made with wheat flour [I get super delicious breads made with whole wheat flour], oats, barley, etc. Unsweetened breakfast cereals, unsweetened hemp, soy or almond milk instead of dairy milk [usually has 1 to 2 heaping tablespoons of sugar per glass]. If you have a diabetic nutritionist available go see one for advice on portion sizes, recipes, and types of diabetic foods available in your area.
Go to your local pharmacy/drug store or Walmart or Walgreens or CVC and purchase a good home glucose test meter. Read the instructions carefully. In order for you to grasp which foods affect your glucose you'll need to test before each meal and 2-3 hours after the meal. Before [preprandial] provides a baseline measurement, after [postprandial] tells you how the foods you just consumed affected your glucose. Start a written log so you can keep track of the foods you can and foods you cannot eat. After a short period of time you'll know which ones to avoid and which NEW foods you can enjoy and be on the hunt for. Good luck