Ok kiddo, back in the olden days in Peru, there was a group of very powerful people who believed very strongly in their religion. They were called 'the Inquisitors' and they were like the boss of the religion. They wanted everyone to believe and follow their religion too.
But, some people had different beliefs and they didn't want to follow this particular religion. Whenever these people spoke out against the Inquisitors, they got punished. The Inquisitors punished them by making them confess to their beliefs and sometimes they were even hurt or punished more. This is what is known as the Peruvian Inquisition.
Think of it like a game of tag where the Inquisitors were 'it' and everyone else was trying to avoid being tagged. But, if they got tagged, they had to confess and be punished. It wasn't very nice or fair, but it happened a long time ago and things are different now.