Keto is pretty much what we used to call Atkins.
As for how to eat, different things work for different people. For me, high protein, moderate fat, and minimizing simple carbs and sugars, while relying on fruit, veggies, and high-fibre options as carb sources is what works best to lose unwanted weight while building/maintaining muscle. If I start to consume processed sugars, white bread, white rice, regular pasta, and white potatoes on a regular basis, I pack on the unwanted pounds pretty quickly.