After you have exhausted other troubleshooting (as suggested by @aceindy) if you have another SD card, install raspberry pi OS and see if the ethernet then works.
The leds are hardware controlled and will come on as soon as the network card is initialized.
yes it’s perfectly plugged
I tried with other router and cables
And no activity shown in any of thoses tests
Don’t you think the ethernet port got fried too ?
If yes how can I set up the wifi on this product ?
So you recommend to do the set up over again with another SD card ?
I’m gonna try that yes 
If there is no light in the leds, then the port is most likely fried.
You can then switch to WiFI, buy an ethernet hat or get an ethernet USB adapter.
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Just throwing this out there, sometimes routers don’t allow all ports to be used through the software.(commercial gear can be set to a bridge mode or a configuration that only enables a single port)
The best bang for buck might be to buy a wifi usb dongle and see if you can get connected that way. Not the best but would almost give you a solid chance to get back on your feet.