行くのか

where … is going

→ 行く
phrase Common #4,395
where … is going Used in indirect questions to ask or refer to where someone is going; the place may be left unstated or introduced by a question word. のか can also express a question or uncertainty.
JA: 彼がどこに行くのか知っていますか。
EN: Do you know where he is going?

行くのか行かないのか。

Are you going or not?

どこか行くのか?

Are you going somewhere?

— ドライヴ (2011)

「馬で行くのか?」

Are you going on horseback?

いつ行くのか教えてくださいね。

Please let me know when you're going.

列車で行くのか飛行機で行くのか決めなさい。

Decide whether you're going by train or by plane.

行くのか?

Are you going?

— ロード・オブ・ザ・リング/二つの塔 (2002)

ここからパーク通りにどうやって行くのか教えていただけますか。

Could you tell me how to get to Park Street from here?

ホテルに行くのか?

Are you going to the hotel?

— レザボア・ドッグス (1992)

行くのかとどまるのか彼の決めるままにさせよう。

Let's leave it up to him whether he goes or stays.

パーク通りにどうやって行くのか教えていただけますか。

Could you tell me how to get to Park Street?