Yes you can.
That hu puts out 18 watts rms and is enough to adequately power an efficient pair of speakers.
There is no reason not to do it though the sound will be limited by the small amount of power sent to the speakers. But for general listening within the power range, push them and the sound quality will degrade fast as well as possible damage to the speakers, they will be ok.
Get a harness kit. It will have the wiring connection diagrams to the existing wiring. Read and connect as the diagram shows. You will use the car's existing wiring, easy peasy.
You don't say if the hu is already installed, nor the car it will go in, or the type of speakers, so this is just very, very basic info.
Good luck and keep us informed.