So you are actually asking about making the wireless router secure, not the laptop. You need to log on to the router using internet explorer. The address should be printed on the router, for example, mine has a sticker on it that says Default Access http:\\192.168.0.1 username:admin password: password. Once you do that you will access your router and need to follow the security instructions on how to change the password your router so that your neighbours cannot log on to it without kowing your password.