The safest amount of weight that a person can lose per week is around 1 lb to 1 and 1/2 lbs of weight per week.
Usually if you do enough exercise you should be able to lose around 4 to 5 lbs of weight per week as long as you eat healthy, get plenty of exercise and stick to your diet.
Some people only lose 1 to 2 lbs of weight per month which is also normal but the more you work at losing the weight the more weight you should be able to lose.
When I was exercising and on a diet and even intermittent fasting I lost around 3 to 5 lbs of weight each month.
The more exercise that I got the more weight that I lost as a result of that exercise.
So make sure you get plenty of exercise and watch the calories you intake and I also recommend fasting or intermittent fasting as it can help you burn fat and lose weight.