British English refers to a "stall" at the market and a stallholder' as the person selling items from the stall. There is an expression "to set out your stall" meaning to state your policy or express your ideas. You could also refer to people selling at the market as "traders" - fruit and vegetable traders,clothes traders etc.

I would say 'stall' instead of stand. I'd call the person a 'stallholder'. You could also simply use 'seller'.

You're welcome, Liao.

thanks your answers!