As a rough guide, you need to match your calorie intake to your desired weight and energy expenditure. That way you shouldn't gain weight or store excess calories as fat. Because you're metabolising them all.
Then you need to decide whether you want lots of carbs, in which case you'll need more insulin, or go for low carb, in which case you eat more fat and protein.
Dieticians will advise on total calories needed but can only give guidance amounts because they can't monitor exercise. You need to eat to your lifestyle.
ALso, alcohol has a high calorie content. And it will generally be laid down straight to fat because of the way it's metabolised and you normally go to bed straight after.
So the first thing you need is your actual weight, then deduce your target weight and work out a total daily calorie target.
And try and fit a balanced diet into that so that you get all your vits, minerals and enough of carb, fat and protein to keep you happy. Including alcohol if you need it.
www.myfitnesspal.com is a good palce to start.
Rob