Yes but and it's a huge BUT. Every single cell in the body can metabolise glucose. The liver alone can metabolise fructose. That's why fructose is uniquely toxic especially in diabetes or pre_ diabetes. It's pretty much guaranteed to give you fatty liver and the metabolic syndrome. Go easy on...
There's a variety of test: OGTT; Kraft (probably the most accurate and definitive) HOMA-ir and hsCRP. Need to ask your endocrinologist/diabetologist what's on offer
It's a bit more complex than that I'm afraid. HBA1c can be low due to massive levels of insulin so everything seems fine but you have the metabolic syndrome in spades. Has you GP or specialist tested you for insulin sensitivity/insulin resistance? Weight loss is only one aspect of the story...
Try to keep your sugar between agreed levels and keep an eye on the projected HBA1c. Essentially if you can establish which foods and food combinations spike your sugar and avoid them you'll do well