Hello @YakubCZ
Thank you for reaching out to us and welcome to the TP-Link community.
Is this the first time you are configuring the router to connect to the internet, or the router was working fine before but stopped working suddenly? It's suggested to follow the troubleshooting guide to check the settings on the router and ensure all are correct:
What should I do if I cannot access the internet through Wi-Fi router?
If the issue persists, please reply with the answers to the questions below:
1. Who is your ISP? Do you still have internet access if you connect the computer directly to the ISP modem?
2. Are the LEDs on the Archer C6 showing up correctly as per the user guide, especially the internet LED?
3. Try to reset the Archer C6 to factory defaults and reconfigure it to check if it can connect to the internet.