Multible Connections with Wireless LAN without Networking

Hmm, sounds like the OP is perhaps just interested in making sure neither device can access the other, yet each can still have internet access.

In most instances, the fact both devices are "networked" (i.e., have the potential to communicate w/ each other) doesn't necessarily mean they can/will communicate. By default, both your PC and tablet are not going share files/folder, access services, etc., unless you specifically permit it. Esp. if they’re using local firewalls (common).

But if you’re still interested in something more proactive, one option that some routers provide for wireless is called "AP Isolation". What this does is prevent wireless users from accessing each other on the network. Doesn't prevent them from accessing wired devices, but will "isolate" wireless users from each other. So if you're only using or concerned about wireless devices, that may be a workable solution for you. In fact, sometimes ppl inadvertently turn this feature ON, and then are puzzled why they can’t access shared files and printers on other wireless devices!

If you also want similar separation for wired devices, then you need a more sophisticated router (to be precise, the switch part of the router) that can create VLANs, which are "virtual switches", each unable to communicate w/ the other, but all would still have internet access. Probably overkill for your needs, but that's what you'd typically do.