Welcome to the forum.
This post should help you a lot -
How To Start Making Money With Adsense-A Basic Guide For Beginners
However, feel free to purchase a domain from GoDaddy but I'd recommend some other company for hosting like bluehost, hostgator, hostmonster or hostnine as cheapest so far.
Moreover, don't expect easy and huge money with adsense right in the beginning. It sounds good but bit tricky to go that far. You should better try in affiliate marketing. That's a far better way to make money online.
Hope this helps you