How to get control the remote accesses for CCTV programming while out of site premises?

As long as the desired operation can be done on the local network it is always applicable to do the same remotely, which would be done on the network level by allowing access in one of the following ways:

1. VPN: where a virtual private network access will get you access same as if you are connected locally, but this would require software and/or hardware on site.
2. NAT: the network address translation present on routers can grant you access to certain devices on the network for  spicific ports and/or port range.

The2nd one is more common for CCTV due to availability and ease of use.