それでは

Placed at the beginning of a sentence, it is used to transition to a new topic or situation.

「それでは」is a term formed by adding the demonstrative pronoun 「それ」before 「では」, in most cases, it can be replaced by 「では」. This is a formal expression; in casual conversation, people use 「それじゃ(あ)」or 「じゃ(あ)」.