Please clarify the details.

Is it reincarnated into a world without magic, retaining all of your knowledge just in a preindustrial revolution knowing and timeline will remain the same minus the changes I make? (Like everything that happened without human influence such as earthquakes, volcanoes, stellar phenomena etc would still happen at the same times, but magic now exists and I don’t have it?

And the other choice. Being reincarnated into a magic world without knowing who I am or anything I knew in my previous life but I will have a magic system to utilize that I’m fully informed of? And also does everyone in this magic world have magic or would I be a rarity or at least uncommon as someone who can use magic?