What kind of license should I choose if I want to play a sound at the fair?
My guess is that the standard license is what you need here. However the license terms do not mention the possibility to play the track at a live event. Maybe something Envato has not thought about? (they’ve been told though).
This specific use could require performance royalties be paid. You should look into who’s responsible for paying SIAE, in case the track is PRO registered.
I think you need the standard license. If you use the track once. For example is the same as to use it once in one video. but if you want to use the track on another occasion you will have to buy it again, etc.