1. your ad setup needs to bee reviewed and verified OK. (this needs to be done! even if you can see your ads. You have to write a description to their team how to see the ad, and they will play your game to verify you use the ads in a good way. Then you can see if you are approved)
2. your actual game needs to be reviewed and released.
then you will need some (a lot!) of impressions/clicks, but you should start to see some revenue..
You can see your statistics in the Monetization Manager.
How you will receive any funds depends how you have set up your payment information.