Why cant you wear nail polish if working at burger king unless its a color that you cant really see and if you do wear a bright color will you get fired?

Most food places won't let you wear nail polish. It could come off your nails and get in the food.

I don't know if you'd get fired the first time for wearing bright nail colors, but certainly if they told you not to several times and you did it anyway they'd fire you for disobeying orders.