My wife and I have gone on and off Keto/Low-carb diets when we start gaining weight and it works really well for both of us I ended up losing ~30lbs in the first four months. I haven’t really had to watch calories at all as the diet itself will usually naturally lower your calorie intake for the same volume of food. I don’t work out at all as I don’t have the time in my schedule between kids, work, and social obligations. I’m a programmer as well so all of my work is done sitting at a desk