Welcome to the forum.
There are many ways and many theories, I can only tell you what works for me.
The others here may have more informative answers for you.
I don't eat ordinary visible carbs. That is bread, rice, potatoes, flour, pasta or anything with those in it.
I eat all vegetables and some fruit, dairy, animal and fish proteins and eggs. I also indulge in the odd sugar-free sweet and drink. I also eat a bit of low-carb bread, currently nimble wholemeal, and low-carb pasta made by Dreamfields.
There are some people here who control their T2 with less carbs, some with more. Read around the threads on carbs and see what you think.
wiflib