"He finally got what he wanted."
Translation:Il a finalement obtenu ce qu'il voulait.
ce que is a relative pronouns like que; that is, it introduces a subordinate clause.
However, ce que is used in sentences in which there is no expressed antecedent. It does not refer to a specific noun, but rather to an idea or an entire statement, which may or may not have been previously expressed: it refers to something unstated and unspecified.
For example, compare it to:
Il a finalement obtenu le livre qu'il voulait.
"He finally got the book which/that he wanted"
For more information see: here