Blood sugar management: How should I manage it properly?

Fasting blood sugar is below 100, but after eating

If measured in two hours, it will be around 140.

It can be said that I mostly refrain from consuming or eating sugary drinks or foods.

Even when focusing on traditional herbal drinks and vegetables, and only adjusting salt intake to low-salt foods, the fluctuations still occur.

I don't eat rice at all, and I eat a little bit of meat...

The increasingly fluctuating blood sugar levels are frustrating.

How are you managing your blood sugar levels?

I am consuming it as a grain-based food.