열으세요? 열리세요? 열려있으세요?
when I'm asking a store or restaurant::

What time do you open?
Are you open?

Question

열으세요? 열리세요? 열려있으세요?
when I'm asking a store or restaurant::

What time do you open?
Are you open?

Answer

You can use 여세요 or 열어요

What time do you open?
몇시에 문 여세요(열어요)?

Are you open?
열었어요(열려있어요)?

Answer

What time do you open?
몇시에 (가게 which could  mean a store or a restaurant)  여세요?

Are you open now?
지금 (가게) 열었어요?