Your body does not multitask well. Neither do you.
A lot of the processes around nutrition (if not all) are driven by hormones. Leptin is a hormone that tells you that you are not hungry, or satisfied. Ghrelin tells your body that you are hungry. Insulin is a hormone that tells your liver and body to get busy storing glucose. Glucagon tells your liver to pull stored glucose and release it in the bloodstream. Since the same organ is responsible for release the paired hormones, you will never get insulin and glucagon at the same time. You are either telling your body to store glucose, or release glucose, never at the same time. You are either hungry or satisfied, but not both.
There was a diet trend, that said you should eat small amounts, every few hours, and avoid being hungry and over-eating. The actual effect is that you constantly release insulin, and rarely release glucagon, and your body is always in the mode of storing glucose. Also, the 100 calorie snacks sold for this purpose tended to be ultra-processed carbs, which just fuels the carb craving cycle.
You can burn carbs, with any exercise, but I think if your body is busy storing carbs, your exercise will burn the carbs in your bloodstream, but will not burn any stored fat. To actually get at the stored fat, you need to fast.
