--Is a cable for power supply included? In the movie, things connecting to peripherals were used. Do I need to make it by myself if I do not belong? Then tell me how to make it.
The adapter cable comes with each one, but it's much easier to cut the wires and clamp under the bolt.

--to shunt the PSU connector to start it up if you are not using enough cards
In any case, you need to pull down the PSU contact to the GND. Without this, the power supply (ATX type) will not turn on.
You can make it directly or through the connector on the board.