Open the inventory window by clicking on a Storage House Then click once on the following items A red triangle will appear in the items square as each is selected
Row 1 item 3 wooden boards
Row 2 item 2 iron bars
Row 2 item 4 wine casks
Row 3 item 1 bread
Row 3 item 5 cooked meat
Row 4 item 1 animal hide
Row 4 item 5 plate mail
Row 5 item 1 axes
Row 5 item 2 swords
Row 5 item 3 lances
Row 5 item 4 pikes
Row 5 item 5 long bows
Then click on Row 6 item 1 crossbow to add 10 of each item to your inventory or on Row 6 item 2 horses to complete the current level