It was determined by the U.S. Department of Agriculture (presumably an objective, unbiased group with no interest in distorting nutritional reality for the sake of selling nutritional supplements) that a well-balanced diet could be optained by an individual consuming the recommended daily portions from the Four Basic Food Groups:
- Cereals and grains
- Fruits and vegetables
- Meat, fish and poultry
- Milk and dairy products
Nutritional supplements were devised decades ago by medical researchers to be used, as the concept denotes, as "supplementation" to correct existing deficiencies for medical reasons. They were never intentended as core elements in the diet for health people consuming well balanced diets.
When it comes to calories, only a few hundred (200 to 400) calories in a surplus or in a deficit (depending on if you want to increase lean muscle mass or lose fat) would be sufficient. Don't do any extreme diets or extreme calorie intakes.
The only supplementation that I would personally recommend is creatine and protein. It is not needed but it can definitely help with recovery and improve performance because taking a 5 grams of creatine is certainly easier than eating 3lb of chicken (3lb of chicken contains about 5 grams of creatine). It should always be used as an addition to the food, not replacement.