Death March kara Hajimaru Isekai Kyusoukyoku (WN) - Book 8 - 8-3. Downtown Disturbance

Calamity descends upon a a tranquil world in the black of night, transforming it into a death game! This a a true apocalypse, but this is not the end of humanity!

- Description from Novelupdates

“Zhong Nuannuan, your charges have been withdrawn. The courts have declared you innocent and pronounced you not guilty for murder. You can leave prison now. Your family is waiting for you in the waiting room outside.” Zhong Nuannuan was startled. She pushed the female prison guard to the side and ran toward the waiting room. She did not even bother to put on her shoes. If not for the icy feeling she felt at every step of the way reminding her that this was not a dream, Zhong Nuannuan would not have believed that she had resurrected.
As she burst through the doors and saw him again, she knew in her heart, that this time she would get it right. This time she would cherish him properly and hopefully, just hopefully, turn her own fate around.

What the heck? She, a famous doctor from the 23rd century, turned into a village peasant girl of a different world!

A teenager named Evan Mason was reincarnated into the magical world of Harry Potter and goes to school at Hogwarts!

With only his knowledge of the future and great talent for magic, he takes the path towards the top of the magic world, only to realize that ever step he took, changed everything!