The numbered door requires a 4-digit number to open.  When the door is interacted with a widget pops up that resembles a keypad that the player can input a set of 4 numbers. To set the correct code I made a instance editable text variable which is checked every time the player presses the confirm button. If the code is correct then a light turns green and the door opens, if wrong a light turns red. 

The powered door simply works by checking if the BP_powerslot has a BP_battery in it. Upon interacting with the battery slot it will check the players inventory to see if it has a battery, if a battery has been picked up the battery will be removed and spawn attached to a component within the power slot blueprint which will open the door and turn the light green. If not, a UI will appear informing the player that they need a battery to power the door. 

The inventory system allows players to pick up and store items for later use (like shown in the powered door video). This was done by creating an array of UI Widgets that when interacting with a pickup able item will search for which widget is empty and put the info of the selected item within including images, amount, and what class.