Well, you register a domain and you could put a web site on the domain.
But for domaining, most people do want to host a site on their domains because it is more expense and work to do so for many domains.
So they create an account with a parking service like Bodis, Imonetize, TrafficZ, or another where they can park their domains.
Parked domains make money be getting clicks and by the amount that is bid for the ads that are clicked on. High bids or more clicks will both increase revenue. Getting 100 clicks for 1 cent each is just the same to them as getting one click for $1.00.
Parked domains get traffic generally in two ways: 1) Type in traffic, where someone types in the domain name in a browser and then goes to the page, or 2) traffic from search engines, or links on other sites.
Most parking companies do not allow you to do ANYTHING to send traffic to your parked pages. But some will allow you to do some things that have no chance of involving fraud. I use one that does not mind if you find places to put links on web sites. People see the links and if they are interested, they click. Some don't mind if you put ads in search engines and have people click that way to you parked domain. That can be tricky because if you pay for clicks to your domain and then the visitor does not click, you lose money.
I suggest learn more about this process until you feel you have learned enough to avoid the common mistakes that most beginners make. You will need to register domains that HAVE traffic, WILL GET traffic from type-ins, or domains that you can work with to start getting traffic to.
