Ceo is a word that means fog or mist, yes. It has no accent, and the accent you've used does not exist in Irish at all.
I have not seen ceo used as a name.
Personally, I think Ceobhrán would make a nice name. It means light drizzle, mist, or haze; alternately, a thin layer. It is pronounced KYO-vron.
I have not seen it used as a name either, but you needn't let that worry you.