Can you specify which smart contract you're specifically talking about? But based on your description alone, it sounds like a typical ponzi scheme. A big no-no if anything.
it is a structure where downline pay upline.
It is million money smart contract on ethereum,you can try to read the contract on ethereum chain
Lol from the name alone it already sounds like complete utter BS. Take a quick Google search on what ponzi schemes and pyramid schemes are, for you to be aware of what you're dealing with here. It's an age-old scam that's being used again and again, just with different ways of attracting people to put money in.