No Internet Access After Unplugging Ethernet Into Laptop And Back In Pc?

So pc is working fine I unplug ethernet cable into laptop to access internet on it,works fine, put ethernet back into computer and now there is no access to the internet. The internet still works as I checked it by plugging it back into laptopThe pc is working all software etc. but there is no internet accesswhen internet works on laptop it says public network but on pc network is unidentified and i can't change it. I tried making a new connection but it asks for username and password and I've never done anything like that. Should i type one in and that creates the password etc. or would i need to have one to create it. I don't really know what the network thing is all about I'm a newb on that part.eI tried network trouble shooter and that didn't help either.