You have been watching too many fake hackers on tv. You would have to replace the router with a device that has the ability to collect and give you the information. It is the only device that can actually see all the traffic going from the house to the internet. It is not a beginner project especially when you want to monitor it remotely.
Any form of wireless inception is pretty much a waste of time to even attempt anymore. All data in encrypted, most routers warn if you attempt to disable it. In addition because of the modern technology called MIMO where multiple overlapping signals are sent it tends to be almost impossible to get good copies of the data even on a non encrypted connection.