@drpokey
Your particular router does not seem to provide that level of control. Without incorporating another device onto your network, there is not much you can do other than setup device based profiles. The DNS suggestion, such as OpenDNS would help limit intenet access and may allow setting blanket rules, but if your goal is to lock down access to your network, you may need to shop for a device that supports that goal.
Another option is to setup a guest network that users can log onto ensuring the check box that gives access to local network is not checked. This would give them access to internet, but not see or have access to any of your local devices on the network. Your model even seems to support setting it up with a portal login, like you would see in a hotel, and give the login a time limit.
Depends on what your goal is.