Firstly I'd check your IP address. If it's a 192.168..... or a 10..... there's no problem with addressing. If it's a 169..... there is. Check you have a default gateway, and if you can ping it, ask the network admin if he's running any kind of proxy for web access.
All this is great if you know how to do it, as I say, I am
moderately computer literate, by which I mean, if you tell me " go to control panel/internet options on your own/host PC and click XYZ" then I can do it ok, just "check your IP address and ping this" does not tell me where to go and what to do. Fairly sure no proxy being run, but not 100% on this (wireless network is on girlfriends computer, set up by someone else).