Physical Disc: If you have purchased Beast of Reincarnation physical disc editions you will have received a code in the box or given at checkout. You can input this code to redeem the items through the "Redeem" button found by navigating to the store on your console.
Digital Editions: If you have purchased a digital copy of Beast of Reincarnation, your pre-order items will have installed along with the installation of the game. You can verify this is installed by navigating to "Manage Game Content" (PS5), "Manage Game & Add-Ons" (Xbox Series), or "DLC" (Steam) by highlighting the game in your library.