If you have no internet connection, start by restarting your modem and router. Check if your Internet Service Provider (ISP) is experiencing an outage. Ensure all cables are securely connected, and try connecting another device to verify if the issue is device-specific. If the problem continues, reset your network settings or contact your ISP for further troubleshooting and support.
Source: https://hackmd.io/@kequery/Howtofixnointernetconnection