[HELP] Authority Site Suggestions

Hello guys , I want to make some quick question before I proceed any further creating my site.

I want to buy a domain name for my site and a custom theme , do have any suggestions any domain seller ?
But I want to use google adsense and the wordpress admin panel for posting , adding plugins.

Is it possible ? And how it is ?

Suggestions guys because I need to learn this baby steps!

Thanks in advance