What exactly is Shengshang Group? Does Shengshang Group do pyramid schemes?

What is MLM? That's illegal! It's not right to go up. I think there are many enterprises with this model now, and their businesses are also very extensive, such as Shengshang, including enterprise listing training, Shengshang new retail, Shengshang charity and Shengshang medical care. I think their leaders often visit and study in famous enterprises at home and abroad. How can such a just practice be pyramid selling?