"Knickerbocker Hospital" in Dying Light 2

To start the quest, you will have to complete the story mission "A Place I Call Home". As a reward, you will receive 3500 combat and parkour points, a recovery booster and 3 first-aid kits.

To start the quest, talk to Ferenc, who is located west of the South Loop radio tower. This is a night quest, so right after accepting it, you can hold down the T key (if it's daytime). Head to the Timing Quarantine Zone at the marked location to the east. It is recommended to go here at night as there will be fewer enemies inside.

Go inside and go down to the first area. Inside the open locker is a pacemaker. After picking up the item, return to the surgeon at the Nut windmill to complete the mission.