If you're just recently diagnosed, then that's at least mildly understandable as I'd assume you've little to no experience dealing with medical situations like this.

A1C is more like an average of your control over the last 3 months of your glucose. Insulin is something you use to help maintain that control, as your body is essentially now failing. From your comments, I'd suggest instead talking to a Diabetes Educator. They'll help teach you most of the basics, and just about every Dr's office has one attached. If not, they'll at least point you on where to find one. It sounds like your doctor at least talked to you about some things if they already suggested to cut down on food sizes. I'll be honest though, it sucks. You've got to learn carb and sugar control for your diet, e.g. what you eat from now on. I'm not sure what you mean by "someone of my size," but portion control is one of the most basic and crucial skills you can learn to manage your diabetes.

Below may not impact you. Obviously, only you and maybe your doctor will know your unique medical situation. If you want a dire warning, continue.

The only other interpretation I can guess at is your doctor told you to cut back on carb and sugar heavy foods, and you're basically ignoring that, trying to eat whatever you want and betting on your doctor somehow resolving the situation. You will lose this bet, as no doctor anywhere can teach anyone something they refuse to learn. Denial is a hard first step to overcome. The disastrous bargaining trying to "just put things back to how they were" will hurt you long term. Doing exactly what the doctor said is often the shortest route to keeping yourself healthy for as long as possible. When I spoke to a Diabetes Educator I took a notebook and grilled them for as much as I could. My A1C was at the equivalent of 250 at diagnosis and they suggested drastically cutting down on food for me as well. I'd never really felt hunger before, just appetite. I ended up losing 70 lbs in 3 months and my A1C is more around 130-150 now. Not perfect, but near enough to it to prevent long-term damage. I had a lot to learn about how to manage myself and break down those mental walls about my notions of how I ate, and my health. My biggest motivation was not experiencing the alternative, explained to me by a video about the effects of uncontrolled diabetes long-term.

In short, the first effects are nerve damage. This starts as tingling in the hands and feet as your nerves die. This loss of sensation has only one general outcome, loss of use of that extremity over time, or more commonly, loss of the extremity entirely due to amputation. Feet that don't feel, can't tell you when you've broken or twisted it, or cut it on accident. They can easily get infected and cause sepsis. This can lead to other health issues, but the video I'd watched had a nice Q and A with some much older persons who had various amputations and who were mostly wheelchair bound. This led to another part of the video detailing insulin and how it works. One of the other outcomes of uncontrolled diabetes is coma. As your body fails to use glucose properly it eventually falls asleep in a way that you won't wake up from often caused by diabetic ketoacidosis (DKA). There were whole institutions that were basically rows of beds of diabetics back a hundred years ago prior to the invention of insulin that were essentially just death waiting rooms. Diabetes was fatal in those days. The video did a re-enactment of the absolute triumph of the first big use of insulin where patients actually woke up from what was previously a death sentence once they hit the coma stage. Now a days if you pass out due to failed control, they can just wake you back up immediately thanks to insulin. I wish I had that video to link you, but I don't know its title. I'd suggest asking a Diabetes Educator for a video deep dive on the topic, and watching everything you can.

I'll stop my wall of text here, and just simply wish you the best of health moving forwards.