There is so much you have not told us.
How much do you weigh?
What are you doing for exercise?
Is your 1,500 calorie per day goal calculated based on a formula, or real life testing?
A formula can give you a rough idea of what your caloric goal should be, but is no substitute for hard work. To do this right you will need to spend time measuring your food intake by weight/volume and content, use a journal to track your calories and macros (protein, fat & carbs), reach a caloric equilibrium so your weight is stable for a month or so, then gradually reduce calories until you are losing 2 lbs of bodyweight each week. In the first week you will lose as much as 4 lbs (this first week's weight loss will include some water as your sugar intake is reduced).
Now, you are ready to get to the part where you fill the gap with carbs. To structure your diet right, you should eat 1.0 to 1.5 grams of protein for every pound of your bodyweight. If you weigh 200 lbs, eat 200 grams of protein each day. That is 800 calories. You should get less than 100 grams fat per day. 100 grams fat is 900 calories. In this example, lets assume you get half that, 50 grams fat at 400 calories per day. If your caloric goal is 1,500 calories your goal of 200 grams protein and 50 grams fat adds up to 1,300 calories, leaving a 200 calorie gap that you can fill with 50 grams of carbs. Voila you have filled your caloric gap with carbs.
Again, all of this gets easier with exercise and a solid base of decent muscle. You should get those right for a year or two, before you engage in serious weight loss.