Losing weight is taking in fewer calories than you are burning; that's what it "basically" is. Exercise is helpful for a variety of things, including (but not limited to) losing weight, but it's not required. I'm burning 1kCal/min just by existing. I can lose weight with no exercise whatsoever by cutting my daily caloric intake to ~1500 kCal or so.
It's true that "starvation mode" is a thing, but your body can only conserve energy to a certain extent: you are always going to need a certain amount for basic metabolic processes, and keeping your brain alive. We can be pretty efficient, but we can't break the basic laws of thermodynamics.
It's not exactly about fewer amounts of calories that one ingests into the body. It's more about what type of calories your body wants to use to perform jobs, work, activity (internal or external).
Different organs have specific jobs to work on. To do these works, they need the calories from specific macronutrients.
A calorie in physics is not the same as the Calorie in food/metabolism. Our internal system's "radars" identifies the Calorie from food differently. 1 radar picks up the readings of Calories from Fat, another radar picks up the reading of Calories from Protein, and another radar can read the Calorie from Carbohydrates.
After properly distinguishing these Calories from different Macronutrients, our body sends them to the right organ to conduct the metabolic work.
Just like different basketball players have different jobs to perform, if your PG is leading your team in BLK or your center is leading your team in ASTs, something is not quite "right".
Or what about in/poor ability to do work? What if your PG is the greatest passer, with the greatest court vision, but he is the worst basketball dribbler ever?
Likewise what if your big man C/PF are the tallest, strongest physique, but they have the weakest fingers and poor dexterity in their hands and they can't rebound or catch the freaking ball?
The Laws of Thermodynamics are accurate in a closed system. The human body is not a closed system, therefore, these physics Laws cannot be accurately applied towards the workings of the human body.
Where are you getting your information from? Because it's flat out incorrect.
There are no "types" of calories in food. A calorie, as you actually stated earlier, is a unit of energy. Excluding the thermic effect of food or energy costs from metabolic processing (which are relatively miniscule), one calorie from lipids has the same energy value as one calorie from carbohydrate.
Your body does not "distinguish calories" and "send these calories to the right organs". This is one of the most ridiculous things I've read and demonstrates that you do not understand the physiology behind nutrient digestion, absorption, and metabolism, nor the processes by which the body produces energy through glycolysis, the Krebs cycle, and the electron transport chain. It distinguishes macronutrients, not calories.
The body's organs run on a mixture of macronutrients, primarily glucose and lipids, with exception of the brain which preferentially uses glucose as a primary fuel (or ketones, in states of starvation or severe dietary carbohydrate restriction). The only other "organ", or tissue that runs exclusively on glucose are red blood cells.
The body is adaptive. Working muscle can catabolize glucose. It catabolizes lipids, and even small amounts of amino acids, such as leucine, for fuel. Other organs are similar in that they use mixed fuel sources. In fact, what your organs use as fuel can depend heavily on what you just ate at your last meal; for example, if you ate a very high-fat meal, your body will increase fat as a metabolic fuel for hours following that meal (this should not be confused with increased caloric expenditure). Take a look at research studies pertaining to meal composition and the respiratory quotient if you're interested. But again, the body does not "distinguish calories and send them to the right organs".
I could give a much more long-winded, detailed post of how most of the things you wrote are incorrect, but it's probably not worth the effort and it would further derail the topic of whether LeBron juices or not. But please stop spreading misinformation if you don't know what you're talking about. There's enough inaccurate - and in some cases downright harmful - misinformation pertaining to nutrition on the internet already.
And yes, weight loss - actual loss of body mass, not water weight - results from negative energy balance. It has nothing to do with "types of calories", which doesn't exist in the first place.
