Good question. It is 2021 and connecting vintage game consoles is definitely not the same especially when theyre from another country!
This will be a basic simple how to. Number one, you need a Famicom. They come in a few varieties. The original red and white Famicom, the grey top loader “AV” Famicom that looks just like its cousin, the NES. In all cases, you need the RAM adapter that goes with the Famicom Disk System disk drive. The RAM adapter sits in the Famicom like a cartridge would and the data from the floppy disk is loaded in to RAM. The cable from the RAM adapter plugs in to the back of the Famicom Disk System disk drive.
The power requirements are unique. You cannot plug in the power adapter that comes with the Famicom Disk System drive directly into the wall here in the United States. Japan uses 100v AC and we use 120v.
Two options: buy a stepdown transformer to use the original power adapter or a special power adapter to use with the Famicom Disk System. The Famicom Disk System disk drive will also run on 6 C cell batteries. The power demand and draw on the disk drive is very minimal and batteries are a very viable solution.