If you have a phone with apps download MyFitnessPal it’s free. You can calculate how many calories you are allowed a day then input everytime you eat or drink and it adds up your calories. There are 1,000s of foods on there and you can scan items too and add your recipes.
It is scarey how many calories you actually consume. You HAVE to be HONEST for it to work but it’s been brilliant for me. I usually exercise everyday and didn’t want to put on weight post op. I’ve actually lost 6lb post op!