Hey i have a nick name given to me at school and when i did my stuff on the registration it accepted it then yall turned around and sent me an e-mail adn said yall declined it please help me get on the site Big Country
The registration process is not automated. The site will take anything, sends it in an email, and it is reviewed by an Admin/trusted assistant, who will accept of decline the application.
"Big Country" assuming that's the Handle you chose, does not fulfill the criteria of sounding like a real name. It is, as you said, a nickname. Simply apply again and try something more name-sounding, in keeping with the rules.
If you want to keep something like your nickname, you could even try "Beeg Coontiree". Stranger ones (IMO) have been accepted. Or you could go for something completely different.
"May the Grace of Ara go with you, and His Vengeance be wrought upon your enemies."