Hello Sand,
The usual phrases are "to be at the helm" (i.e. to be the person in control of things, like the helmsman on a ship), or "to take the helm" (i.e. to assume control of things).
They tend only to appear in statements; in questions, they might sound a little sarcastic or humorous. But if they did appear in a question, you would say e.g.
1. Are you at the helm?
2. Have you taken the helm?
Best wishes,
MrP