I think you need to get someone a bit better with electrics to advise you on site. I'll try but your basic knowledge seems a bit shaky.
The usual way to connect a PC-type speaker to a computer is via a standard lead that has two RCA/Phono sockets on one end (the speaker end) and a small Walkman/MP3 headphone style jack at the other (computer end).
The Walkman jack goes in one of the small round connectors (usually) at the side of the laptop case (see manual for computer ?)
The PC-type speakers are probably powered by a transformer (perhaps inside one of the speakers) which is connected to the wall socket.
Be very careful you don't get mixed up about how to connect to the wall socket, though the supplied leads should prevent accidents.
If you can't get help on site, I suggest you obtain (perhaps from the maker's website) the instructions for connecting the speakers and study them carefully.
It's really pretty simple but I appreciate, if you don't have 50 years experience of messing with wiring like I do, maybe it is confusing.