Some people on a keto or low carb diet choose to count total carbs instead of net carbs. This makes it more difficult to fit in more leafy greens and low carb vegetables (which are filled with fiber), so you should only try that if you don’t get results with a net carb method. And, start with reducing sugar alcohols and low carb treats before deciding to do a “total carbs” method.
A ketogenic diet plan is not a "special diet" that requires special foods. There is no need to buy any "low carb" packaged foods. Ketogenic foods are essentially just real, whole foods which are close to their natural state. In other words, they are not highly processed. The only exception to this is the category of artificial sweeteners. These are highly processed. However, I think these are important to include in a low carb diet plan, because a small amount of fake sweetener has less of a negative effect on health than the standard amounts of sugar in sweetened foods. Some people may prefer more natural sugar alcohol sweeteners, but studies have shown these are "antiketogenic" and can derail the process of ketosis for some. They effect each person differently, so you'll have to test to see if they effect your health or weight loss goals.
The brain is composed of a network of neurons that transmit signals by propagating nerve impulses. The propagation of this impulse from one neuron to another is typically controlled by neurotransmitters, though there are also electrical pathways between some neurons. Neurotransmitters can inhibit impulse firing (primarily done by γ-aminobutyric acid, or GABA) or they can excite the neuron into firing (primarily done by glutamate). A neuron that releases inhibitory neurotransmitters from its terminals is called an inhibitory neuron, while one that releases excitatory neurotransmitters is an excitatory neuron. When the normal balance between inhibition and excitation is significantly disrupted in all or part of the brain, a seizure can occur. The GABA system is an important target for anticonvulsant drugs, since seizures may be discouraged by increasing GABA synthesis, decreasing its breakdown, or enhancing its effect on neurons.
When you lose weight, fat cells shrink. In a fat cell, there are triglycerides and cholesterol. Now, as that fat cell shrinks, you can burn triglycerides, but you cannot burn cholesterol. So it will go into the blood, go to the liver, and come out through the bile. But you’ll be totally fine as long as your triglycerides are low. (If you’re not using those as fuel, then you’re eating too much sugar.)