On a ketogenic diet, your entire body switches its fuel supply to run mostly on fat, burning fat 24-7. When insulin levels become very low, fat burning can increase dramatically. It becomes easier to access your fat stores to burn them off. This is great if you’re trying to lose weight, but there are also other less obvious benefits, such as less hunger and a steady supply of energy. This may help keep you alert and focused.
While macros will differ a little from person to person, the general rule of thumb for keto is to keep carbohydrates under 5% of your daily caloric intake. As long as you avoid the foods mentioned above, you should be fine. Google “TDEE calculator” if you need some additional guidance on how many calories to eat. I’ve had success following this way of eating as it allows me to eat foods that taste great. There are tons of resources online as well if you need additional guidance. A quick google search should turn up a ton of resources. Hope this helps!