Yes, it is free. The idea is pretty simple. We all buy into a coin when It's cheap. When people start noticing it will take value. Then you can sell when you are satisfied with the profit you have made.
But for this to work we need to have enough members.
This can be done without this ,but it will take time to noticed. In group there are better way cuz more eyes are on this. But most users here are skeptical about it cuz it has been here noted that many groups were scam or they want money in advance. Will see how will you go.