go to dock, click storage. then move then 1 at a time. have a look at your storage capacity, up may need to move from storage to doc first. If your full then you can move 1 hull at a time
If you maximize dock to level 16 and War Academy to 20 you can have a max ship storage in dock of 130 ships, max storage is 110 ships. You don't need all the kix free fleets unless you don't have your Praetorians or Everests built or upgraded. Usually the duplicate fleets for me become resources as I scrap them right before a ship build to overfill the warehouses (max capacity on overfill is 2 billion of each, not including uranium, base parts, or titanium).