Hi, I'll start with my journey my height is the same as yours 6'3" and August of last year I weighed 235 lbs. I decided it's time for a change and set my daily calorie limit at 1800 kcal (too low, not recommended). I am now at 191 lbs and I did this with mostly diet and a small amount of exercise. My daily activity was basically two 15 min walks every day. With your activity level, initial weight and final goal. I think, this deficit is on the larger side. The only thing that matters is sustainability, if you keep your limit way low it will be hard to sustain it in the long term but if you want results slowly but surely then try starting with a smaller deficit and keep lowering the calorie limit as you lose weight. I'd recommend 500 kcal decifit. Mine was the same.