I'm a skinny fat guy. Height: 184 CM, weight: 81 kg, body fat: 15%, Shape: shitty. Right now I started lifting heavy, and I'm following a maintenance calories intake. But, I don't know how to setup my macros ratio.
Honestly a lot of this is down to the individual (e.g. You)
General recommendations tend to lean towards a protein intake of around 0.8 - 1g per lbs of body weight, so if we say you weight 178lbs, then that's a daily protein intake of about 142 - 178g, push that towards the higher end if you're doing heavy weight lifting.
For carbs and fat, I'd start off with an even split based on your remaining calories (so, assuming a 2500kcal intake, and 170g protein (680kcal), then you'd want 910kcal of carbs and the same of fat, which equals roughly 230g carbs, and 100g fat).
I say start off with, because different people react differently to different carb / fat ratios. Some people do really well on a high fat / low carb diet, others find better results on a higher carb / low fat diet.
Pick a ratio, try it for a few weeks and see how you feel on it, then try nudging it one way or the other.
One strategy that I do like to figure out which way to adjust is to make yourself three lunches, a balanced one (as above), a high fat / low carb one, and an low fat / high carb one, have one for lunch each day and see how you feel in the afternoon. If the high carb / low fat lunch leaves you curled up asleep under your desk, but the high fat / low carb one gives you laser focus and makes you feel like you could run a marathon, then chances are you response better to high fat / low carb.
What is more important than your exact macro-nutrient ratios, is finding a dietary strategy that's maintainable for you, consisting mainly of whole foods (meat, fish, eggs, vegetables, fruit) with very little packaged or processed food.
I'll restate that because it's honestly the most important part of all this, the quality of the food you eat is much more important that sticking exactly to a specific macro-nutrient ratio.
There's a lot of "right" macro values. If anything it's a testament to the flexibility of the human body and what it can handle nutritionally. I'm going to base this discussion around the assumption that you're starting a proper strength training program which is proven to be very effective for fat loss, including compared to aerobic exercise.
I'd start with a macro calculator which will put you in the right ballpark. Just looking at mine, at 180 pounds it says I need to eat 232 grams of protein. Double checking the math on that with Lyle McDonald's guidance, he recommends 1.1 g/lb - 1.4 g/lb for strength trainers and body builders (basically folks who need to do a lot of muscle repair and growth).
The IIFYM calculator linked above puts me at 1.28 g/lb , so I'm smack dab in the middle of Kyle's range.
Once your protein is figured out, next up is carbs and fat. Things can get fairly religious here, with keto eaters eliminating nearly ever carb they can, and other massive strength athletes never shying away from bowls of rice and cereal.
I'd start by sticking to the macro calculator for your fats and carbs, and adjust as you see fit. In general most people should cut back on their carbs: they're just way too easy to consume in a western diet. Also, they tend to be "junk carbs" with little nutritional value other than calories (flour, white rice, etc). And fats should be high quality fats, like olive oil, almonds, and fish. Not bacon, lard, or really anything else solid at room temperature. This is why it's a little short sighted to say "fats are better than carbs".
Black soy beans as an example have been extensively studied and shown to have numerous positive health benefits. To throw all of that away and eat bacon in place of it is shortsighted. Further, both high and low carbohydrate diets have shown to lead to reduced life expectancy.
Wrapping that all up:
- Use a good strength training program.
- Start with a macro calculator.
- Get your protein right.
- Eat quality carbohydrates, quality fats, and vegetables.
Protein value is based on what a body needs to construct muscle if you are weightlifting (2gr/kg is recommended), Fat value is based on what your hormones needs to function properly (1gr/kg is recommended), Protein and fats are essential so after that total, you can calculate your carbs (1 gr is 4kcal), based on your daily intake!
So if you know your intake my number are pretty decent I think, but If I was you I will start with a mini cut, same macros but with a lower calorie intake, to avoid as much as possible muscles loss and to get a decent bf, and then lean mass
Proteins : 2.2gr / kg (A little bit high because with your bodyfat it's better to eat protein calories instead of fats or carbs calories)
Fats : 1gr / kg
Carbs : Rest of your calorie intake
Some people will say "Science says your protein number is too high", yeah science said that, but in fact here, science doesn't matter, proteins and fats are essentials, have a "high" protein intake is not a problem for your body, it's better to reach your calories with proteins instead of fats or carbs to lean mass especially with this body composition
To resume yes 2.2gr of protein is useless to build muscle, but here we focus on losing fat ( Source )