Can we connect different networks using switch without a router



You can't connect to a wireless network with a switch, that is for a wired network and only connects everything without any ip assignment or routing capabilities. That stuff could be done by a server OS, but I would not suggest that since you don't know much about the subject.

You can use multiple wireless networks (one at a time) by disconnecting from one and connecting to another on the computer with the wireless adapter.

If one computer has several wireless adapters you can bridge the networks on that machine, and as long as the bridging machine is turned on, the various networks can be shared.

None of these ideas is very practical though. What are you actually trying to accomplish? Why can't you just put all the computers on a single wireless network?