Welcome to the forums, newcomer!
You might want to start by specifying how you're tethered to the internet via the Ethernet cable...? Router as your intermediary or a device from ISP to your laptop/desktop? For the latter, check to see what the BIOS version on your motherboard is. You can then check to see what OS version you're on(assuming you're on Windows 10), then reinstall your networking adapter's drivers in an elevated command, i.e, Right click installer>Run as Administrator.