Actually it is not as complicated as it looks. You just read a lot of info.
A mother board connects to the pc via a printer cable.
An Rj45 cat5 cable connects between an encoder adapter or a differential encoder and the drive.
You need a power supply for the motors (as shown in the motor and drive matching document)
You need a simple 24 vdc power supply for the logic on the drives.
All the other stuff is pretty simple or optional.
You do need to select motors within the range of the drives. Again, the motor and drive matching document is designed to help with this.
I hope this helps.