
While progressing through the story of Resident Evil Requiem, both Leon and Grace gain access to a wide variety of weapons, each with its own characteristics. However, Leon has access to a special mechanic: the Supply Box. This allows you to obtain special weapons and items... in exchange for eliminating enemies.
To unlock the Supply Box, you must progress until Chapter 10 (warning: spoilers in the link). While progressing through this area, you will eventually need to explore the Central Camp. Here, you will activate a generator to restore power and examine a computer. After doing so, you will see the Tactical Tracker to your left.
Interact with the box beneath the Tactical Tracker. This is the Supply Box. From this point onwards, you will earn Credits by eliminating enemies, which can be exchanged for items at the Supply Box. You can also purchase upgrades for Leon's weapons from the Supply Box.
These are all the items available from the Supply Box, along with their prices in Credits and any requirements you must meet to unlock them:
On Madness difficulty, the prices are different and Level III Body Armor is also added.
In addition, you can use the Supply Box to upgrade weapons and obtain Leon's special weapons.