I haven't even started my day and I'm already at 700 calories, at the end of the afternoon more than 2000 calories without doing any exercise, how do I reset or adjust the calories?

Check your body parameters in the settings, especially the weight (but also the height, age, and gender), and then check out your Resting HR as shown on the HR panel, and the Max HR as found in the user settings. If they are too low, it would lead to excessive Calories counts. And, of course, also have a look at your all-day HR data, if the HR is unusually high during the day, the Calories will be high too.

What is your normal resting calories for a full day? Swipe back one day and look what the result for yesterday was.

My resting calories every day is 1976 kcal. That will give me 1976/24 = ~82 kcal/hour. When I wake up at 7 in the morning I will have used 7 x 83 = ~576 kcal. That will be the resting calories at that time no matter if I've had the watch on me or not. That is what keeps me alive. It is the cost for breathing etc.

When you get older and/or change weight the resting calories will change, but not with very much.

Resting calories - "Your resting calories are calculated using an estimate of your Resting Metabolic Rate (RMR). This is the number of calories you burn while performing basic functions like breathing and circulation. RMR is based on your age, height, weight and gender. To determine your resting calories, we slightly increase your RMR estimate to account for sedentary to light movement throughout the day."

Calorie Terminology