In order to unlock this quest you need to first have visited the Liberty Museum and helped the people trapped inside. After that you go back with them to Sanctuary, where you are asked to complete small tasks about rebuilding the village.
- Build beds for the people in Sanctuary.
- Get clean water for the people in Sactuary.
- Provide food for the people in Sanctuary.
- Secure the perimeter by building defenses.
For the beds you need steel and cloth. These two materials are easy to find inside the village, just dismantle cars or couches.
For the clean water you will need concrete, which is found after breaking down the ruined houses inside the village too.
Behind the house with the tool tables there are melons, pick them up and plant more of them. Explore outside Sanctuary (around Bedford Station), there you should find some multifruits and carrots that help. In "building" mode click a person and then assign him/her to cultivate the plants.
Create some defense structures ( the first two since you need circuits for the others) and assign another person to the task.
- This serves as a introductory quest into settlement building.