What it means
か何か means “or something” and indicates that the speaker is intentionally leaving the exact identity, choice, or action unspecified. It can follow a noun or a plain-form clause, often when making a tentative guess or giving an imprecise example. The expression can sound less direct because the speaker does not state the precise information.
Usage note
In か何か, 何か is part of a fixed expression meaning “or something.” This use should not be confused with the independent pronoun 何か, which can mean “something” or “anything,” occur with particles such as を or が, and modify a noun in expressions such as 何かの理由.
How to use it
彼は医者か何かです。
He is a doctor or something.
彼は鍵をなくしたか何かです。
He lost his key or something.
彼は医者か何かだ。
He is a doctor or something.
彼は鍵をなくしたか何かだ。
He lost his key or something.