I started on Sunday as well! Which also makes me a complete newbie. I'm pretty sure that it isn't required for you to eat all of the designated calories. The number of grams of protein is your goal, so you should definitely hit that total. You don't want your body using your muscle mass as fuel because you haven't eaten enough protein. The number of grams of carbohydrates is a limit, so you can eat up to that amount but it isn't required to fulfill it. And then the number of grams of fat is an "as needed" amount since your body's fat is what you actually want to burn, so you should eat it to satiate your hunger. It's very possible that I'm not 100% correct, but I have read it in a number of keto resources!