My mind is blown How do I add an inventory slot?

- Inventory gui slot numbers minecraft inventory slot png a png by me! pls dont take credit 3 original image here: comimgres?imgurl=h… Image size 633x633px KB minecraft inventory slot Minecraft displays the player inventory differently, according to how the window was opened Ranges of slot indices vary in meaning between

minecraft slot png Minecraft displays the player inventory differently, according to how the window was opened Ranges of slot indices vary in meaning between