To what did Tituba confess? why?

She wants to get a reprieve from the beating she is receiving. Parris won’t let up. She also knows that if she confesses, the court might have mercy on her because she validates their existence. Tituba knows she can implicate others so that the court will be more lenient on her: Tituba is pretty clever!

She wants to get a reprieve from the beating she is receiving.