Based on my understanding of your query, we can assume that you might have the wrong settings for your WAN interface.You can investigate by the below methods,
1. Connect your LAN cable directly to your Laptop and see if you are getting internet connectivity. If not most probably you have other settings for WAN like PPPoE and so you might need a username and password from your ISP.
2. You can also log in to your old router to check the internet settings.
Regards,
Clive Pinto