I love Keto. I ballooned up to 315 lbs at 5' 9" and was miserable. Being hypocaloric is one thing but to fight the glucose storage to eventually burn fat is another. Don't follow or even pay for any paid for program. Plenty of free and legitimate information sources to accomplish an effective Ketogenic style (Like myself). When strictly cutting the fat doing straight Keto is the best. If you are an avid lifter, follow through, and stick to the program then Cycling and timed specific carbohydrate intake is best approach.
I tried to keep it simple for myself. I ate a lot of Broccoli, spinach, Brussel spouts, cauliflower along with chicken, beef, lamb, liver, turkey and fish. I used grass fed butter like Kerigold and also supplemented with coconut oil for the MCT to keep my fat intake up.
One mistake that is most commonly made with Keto style eating is the lack of fat. If you do not consume enough fat you will enter Gluconugenisis. Your liver will take the excess protein in ratio and manufacture glucose out of it.
When you deplete your glycogen storage from your muscles and liver you enter a state of Ketosis. This is where the body makes the Ketone bodies from the fat. When you are in Ketosis you have a more direct supply of energy from the fat. It is also just at easy to store it as it was when you were not in Ketosis.
Calories do matter on a Ketogenic diet. You need to be hypocaloric but instead of the times you are hypocaloric depleting your 200 grams of stored glycogen to compenstate it taps the fat as you have become fat adapted during Ketosis. So you burn 3000 calories and consume 2500, you burned 500 of fat calories since there was no glycogen available to burn. This is where the plan excels.
During this time you will not have much insulin. It will help increase your insulin sensitivity so when you are ready to reintroduce cyclic carbohydrates for resistance training they will be more effective and you will feel the muscular pumps. This is based on my personal experience.
I could dabble more and do a more detailed write up as a power lifter, soon to be again bodybuilder, and formerly Obese person.