Like others have said, it’s speaker wires. That’s not what you’d used for electrical wiring. Nothing wrong with being cautious and checking for voltage with a multimeter, but those are most likely speaker wires.
The reason there are probably so many wires is they may have had a stereo receiver located there for patio audio or something similar with a cable box as one of the inputs on the receiver.
You might look into buying a tone and probe kit if you are having trouble locating the wires. A toner runs an audio tone through the wires and the probe wand has a speaker that helps you hear and follow the sound that runs down the wire.