Hi saurabh ,

Yes you can definitely take a visit as a outsider but during office hours it would be a bit boring for you as IIT kharagpur campus is large enough and if you dont have any friends over there then you will be just left alone in that large space . I once had visited IIT kharagpur but I had friends over there so I really enjoyed at there courtyards at somr areas you will get restricted to enter but most location permission is provided.

Hope it helps!!!