This is the 1449th most frequent German word.
neues
"Neues" means "new" (referring to something in a neuter form).
Here, 'neues' acts as an adjective describing the noun 'Book', indicating it is new.
Ich habe ein neues Buch gekauft.
I bought a new book.
In this case, 'neues' again serves as an adjective, qualifying 'Member' as new.
Wir haben ein neues Mitglied in unserem Team.
We have a new member in our team.
'Neuen' serves as an adjective modifying 'restaurant', adhering to the grammatical rules of the object's case.