What you need is a DVR with networking capability. Sending video wirelessly is not advisable since the signal can be subjected to interference. The 2.4GHz band is very crowded.
You can get more info about the DVR from major vendors: Swann, Lorex, Q-See. Make sure that the CCTV cameras have the same connection (BNC, RJ45, or RCA) that matches with DVR. Also where the DVR is located need to have internet service.