Create a WordPress Template

Greetings, I want to add calorie counter page to my Wordpress blog. website visitors should able to type food they eaten, with serving size and website should give back the information about calories. For example: I eat 2 apples for breakfast, 1 bread for lunch, 1 pineapple for dinner. I visit page, fill up the information. Breakfast: Apple - 2 fruits (choosing from whole foods, grams, slices) Lunch: Bread - 1 slice (choosing from grams and slices) Dinner: Pineapple - 1 slice (choosing from whole foods, grams, slices) Finally it gives information about summary of calories - you eat X calories today, X fats, X carbohydrytes, X protein. If it appears that server doesn't have calorie information about any of this product, it suggest to send information to website owners to add product to the base For owners it should have following functions: • adding new products with calories, fats, carbohydrates, protein • choosing from several options to measure product. For example, if 1 apple has 100 calories, we should be able to set calories for other measurement options too. 5 slices = 1 apple = 100 calories, 2 slices = 40 calories. • getting information somehow about non existed products, it doesn't matter if we get this info on mail, or in admin panel, which is easier. What could you offer us?