These mobs are specific to the education edition, and either need to be summoned or spawned.
Non-Player Character (NPC)
It is common to see NPCs through a predesigned world. They can provide written direction, instruction, clues or information. They can also run commands. Students and teachers can place their own NPC into a world. Before doing this, you must be in World Builder mode. This is achieved by typing the following command into the chat:
Ensuring that you are in creative mode, retrieve an NPC egg from the inventory and place it into the world. Selecting the NPC will allow you to change the skin and enter text and commands.
The agent is a non-player character designed to support the process of teaching coding in Minecraft Education Edition. You will commonly see the agent featured in the Hour of Code world, and it will appear automatically after opening the code builder software in the game.