Lewis is usually a surname. In English, the former is a given name and the latter is a surname. Example:
Daniel Day Lewis (Daniel Day-Lewis) Oscar Best Actor
Donna Lewis (Donna Lewis) is a British pop singer and songwriter
But there are exceptions, such as: McLaren driver Lewis Hamilton (Lewis Hamilton), known as a super rookie, has suddenly become popular since last year. After that, he became the new darling of the media among F1 drivers, especially his hometown British media who focused on him in almost every race.
About the meaning of this name:
Lewis, 1. Lewis is derived from the Norman name + Germanic language, meaning "fame + war", 2. The name of the place, derived from ancient times Snow language, meaning "silent" (refer to English name dictionary)