Can you use "still" in the beginning of the sentence?

See a translation

Depends..

"Still waters run deep.."
"Still, you shouldn't take my money without asking ばか！. "

I suggest you provide example sentences when you ask questions because some words have multiple meanings.

"Still an interesting question."

I think you meant in the case where a sentence like that 👆 where

"it's still an interesting question."

gets shortened to

"Still an interesting question ."

👆That's an example of a sentence fragment (It's like you cut off a sentence midway. ) I think. they are used a lot in conversations but are not that grammatically correct I believe.

But.. If you add a comma the "still" acts as emphasis

"Still, that's an interesting question."

It's a highly debated point how appropriate it is, so I would say if it's formal/academic writing you can avoid it. But otherwise it's accepted.

Twisted answer. Hope it makes sense.. It's like 11pm lol