This part of the Guide Fallout 4 is dedicated to the Institute's quest "Homecoming". Father tasks you with finding a synthetic who has taken control of a band of raiders.
Condition: Join the Institute during the quest "At the heart of the Institute"
Immediately after the end of the quest “At the heart of the Institute”, visit Father so that he gives you new objectives (picture1). At the end of the dialogue with him, reach the point indicated on the map and discuss with X6 before attacking Libertalia (picture2).
Once you have managed to reach the bastion of the leader of the raiders, go upstairs and talk again with X6 (picture3). Then climb on the roof of the building to find your target, here, immediately give him his recall code to deactivate him and then kill his two lieutenants (picture4).
After X6 leaves, return to Father to give him your report, then follow the quest marker and enter your quarters to complete the mission and receive your bounty (picture5).