In addition to what @Marie20 stated above, many people, usually adults, are assumed to be T2D by their doctors based mostly on their age. This may not be true for you and your recent course of Covid-19 complicates things.
The links that Marie provides to Diabetes Forecast are very good sources for factual and dependable information.
Another resource from a long-term TuD member, @Melitta is a great one to explore. Here’s a link to some solid information:
Blood sugar levels in the 290-450 range do harm health. Effectively treating those abnormally high glucose levels should be job 1 and if it takes insulin to accomplish that, then so be it.
I’m sorry you’re struggling but I do think you can turn things around and feel much better. Good luck and please report back when you learn more.