You should be able to use either a USB/Ethernet adapter to connect to the router using a USB port on the PC
or
by using a PCIe ethernet network card to connect PC and router via an Ethernet cable.
Just ensure that all other network adapters (e.g., onboard ethernet adapter and wireless adapter (if present) are disabled.
Be sure to download the necessary drivers via the manufacturer's website, install, and configure the adapter as applicable to your router and home network.
Did you purchase or otherwise get another router? If so, I recommend that you purchase the network adapter from the same manufacturer.
Before you buy, take the time to read the applicable installation and configuration instructions via the Quick Start...