Register Domain and automatic parking in default page.?

Hi guys, I'm new in WHMCS, I love it this platform, my hosting is ready and working, I have a question, I tried searching on google but I get nothing, My WHMCS is configured with enom, everything is configured correctly with my DNS NS1.MYDOMAIN.COM NS2.MYDOMAIN.COM. each time a new domain registration automatically registers with my DNS, my big question, I want that when someone tries to go to a domain registered by me and not have hosting service, just registered and my DNS, will display a default page from my hosting.? please as I configure this.? Please Help.!

Thanks in Advances,
Manny R.