Why No Net Obtain when connected to Wi-Fi ? WAN port is unplugged in TP-Connection Wireless Router

I can connect to Wi-fi Community, but there is No Net Acces, why?.
LAN port of Broadband modem is not connected to WAN port of Wireless Router. So there is no Web Accessibility.
Check out your wireless router’s WAN port, you can see the message WAN port is unplugged.
When you troubleshoot difficulty, Home windows Community Diagnostics will detect the adhering to troubles:
Home windows cannot connect with the system or useful resource (key DNS server) – The unit or useful resource is not responding to requests.
The DNS server is just not responding – Your laptop or computer is making an attempt to use a DNS server that is incorrect or would not exist.

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