no way to find any instruction on how to

install a radio player on my new fabia-w.

not a word in any of the provided book!

do any of you know someth'bout?

radio? or aftermarket CD player?

If its a Skoda one, it should just plug & play using the ISO connectors (follow same pattern as existing one) If its an aftermarket CD player it should come with ISO adaptors to to the same trick. If not, you may have to toddle down your dealers to find out the wiring diagram for the wiring in the car, and use whatever manuals you got with the radio to match and join them up.