i dont know whats happening but some "hacker" knows my ip and started guessing where i lived and told me my postcode and im freaking out, can he hack into my wifi though?
Just the device they hacked. They can read every information on your device, location, where you live, credit card and debit cards everything. If this is nework hack and has access to your wifi, the hacker can travel between multiple devices. Usually getting a new ip address is the best way to go. Make sure you have powerful antivirus like trendmicro keep hackers at bay.