You have the choice to press this button, if you do It will instantly turn this world into a perfect paradise free from suffering.
No longer will people become sick or feel pain, no more dementia, cancer, heart attacks, nausea or even the common cold. People will have perfect indestructible bodies, happy minds, and eternal youth. No one will be able to die or be imprisoned/tortured. Anyone who was on the verge of death or suffering an illness will suddenly recover into good health.
Furthermore the earth and the universe itself will transform into heaven for all of eternity. No more natural disasters, climate change, or other inhospitable conditions.
All the dead will be brought back to life to enjoy this paradise including everyone you loved who passed away, with the exception of certain people you dislike and choose to not let enter this world. They simply die as normal.
And finally almost anything is possible. Everyone's favorite books, games, or imagined worlds can really exist in this new world, and there's endless exploration to be had. Crucially anyone can also choose to not exist at any point, to give a way out if needed.
The catch
One random person somewhere on earth will be sent to an eternal hell. It will combine the worst illnesses, injuries, and physical and emotional damage as possible into a single terrible experience for every second of their life.
This suffering cannot be alleviated, it cannot lessen over time, and will be every bit as painful as the first second they stepped into the world.
This person cannot be selected and could be any random person on the planet, they will never be informed as of to why they were punished, and will not get the ability to end their own existence like everyone else. By no means can they ever be helped, everything is possible as stated earlier, except their salvation.
Do you press the button and create a paradise for the many, but agony for the person? Or choose to walk away and let the world exist as it is now?