Will Books Sell Even Tho Your Not Famous?

lets say someone writes a book will they sell that many if there not known ? like first time book publishers? & Also lets say the person got on a hit reality Show & grows a fan base, will they sell more? & Would it be Smart To Sell The Book While The Season they are on, on the realty show are Airing Or Sell AFTER there season is over? LEGIT ANSWER