When the ship is loaded you can add the cargo by clicking on 'Add Load'.
Then enter the name of the load and the quantity. If it concerns a load such as containers, you must also enter the number.
If the ship has another cargo, it can be added in the same way.
You can always remove the load by clicking on the trash bin.
IMPORTANT:
APICS Barge takes over the cargo from the previous voyage within the same stay. Don't forget to adjust the load if it changes!