Step 1 - Add inventory component
Add a inventory component to the character.
Initilize the component on BeginPlay. You can use “Init Component” and check “create default slots” to create a empty inventory or use “SERVER // Init Component and load inventory” to load a existing inventory.
If you dont want that a client can load its own inventory, change the function to not replicated and load it only on the server.
Step 3 - User Interface
Create a UI on the client and add it to the viewport. Initilize the widgets and send the UI Reference to the player controller via the “Inventory Interaction Controller” Interface. (see BP_Character_InventoryExample -> BeginPlay)
The inventory manager need this to open close widgets.