I don't know for others but I find question like this very annoying to be honest. Someone refer you here and you can not ask them what this place is all about? They're supposed to give you details information and how to explore the forum. It's obvious you joined purposely to earn which I believe it is the same reason as your friend. Let him sit you down and explain how things work here.
However, you are here and of course we have to welcome you. Several links have been recommended for you and I assure you that reading them will definitely guide you to every aspect you need to know about the forum. But remember this, coming here with the mindset of earning will make you feel as you are wasting your time at this early stage.
Sometimes I'm tempted to believe that it's because of what people stand to gain that's why they registered here and with how this "I was referred to this place by my friend" line has become so widely used, it's beginning to sound lame and like a lie and there wasn't a friend but for a lack of a better way to introduce themselves to this place they use it.
Heck, just like you mentioned, the referee tells them what they can gain from here but refused to show them how to go about it? SMH!
Probably this 'friend' feels they've got some magical power that can enable them flourish here without knowing nada about how the place operates and functions? Great..