Hi @salimreza11122s    

Thanks for reaching out to us. 

May I know what is the model number and hardware version of your TP-Link router? 

If your TP-Link router can't connect to internet firstly, please connect your computer to your modem bypass TP-Link router to check if your modem has internet or not. 

If your modem is working fine, then please connect TP-Link router back to the modem and refer to below guide to troubleshoot:

What should I do if I cannot access the internet? - Using a DSL modem and a TP-Link router

What should I do if I cannot access the internet? - Using a cable modem and a TP-Link router