Look at manual of speakerphone and put it in pairing mode. Then open Bluetooth options on your phone and it should "see" the speaker. Click on it to pair
Did your car or Bluetooth "speakerphoneCK21" come with an owners manual with Bluetooth pairing instructions? If so, that would be the best source of information regarding this matter. All I provide is generic information: make the iPhone and/or speakerphoneCK21 discoverable and then pair them together via the iPhones Bluetooth setting.